Critique of Mid-to-Late Game Progression, by SillySMS
Posted: Wed Dec 21, 2022 8:10 am
This is a long form critique originally posted on another Discord by player SillySMS. I am posting it here on his behalf, as the forum is more appropriate for long form critiques.
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Abstract
Current game balance and progression in Terra Invicta is dominated by two major factors: poor alien AI and an exponential increase in mission control availability once command centers are unlocked. The first makes the aliens feel unsatisfying as an opponent, and exponential growth in player capabilities throws any difficulty out the window once the exponential loop gets going. After you are able to put down significant numbers of command centers, the first endgame is a victory march, and subsequent endgames are boring slogs to polish off aliens who don’t yet realize the situation is hopeless.
Introduction
As I understand things, mission control and alien hate were introduced to keep players from going von Neumann (i.e.exponential growth) and trivializing the game.
However, as implemented, this merely delays the transition to exponential growth, thus putting all the difficulty into surviving up until a sharp transition to overwhelming power, a point shortly after researching command centers.
Exacerbating this is the combination of nominally overwhelming alien power and the sheer ineptitude with which that power is wasted by the AI. The aliens may outnumber your ships 10:1 with a major tech advantage, but that doesn’t matter if they send out penny packets to be dismembered by hab defenses and the occasional fleet to be destroyed by player point defense walls. The flipside is that if the aliens were made competent without any other changes, it would be extremely difficult or impossible for the player to win because of that overwhelming technological and infrastructure advantage.
Furthermore, the player is limited by a combination of limited mission control and inefficient drives during the early game, favoring passive gameplay until command centers alleviate MC limitations and space research swiftly clears out the tech tree. It is very difficult to spare the hydrogen and mission control for a mobile campaign, and easy to instead let the alien ships suicide themselves against static hab defenses and your Earth defensive fleet.
This leads to three phases of gameplay: a passive phase where you build your initial infrastructure, a defensive phase where you exploit AI weaknesses to preserve your infrastructure, then once command centers are available, an offensive phase where the player just tips a gigantic pile of research, space resources and mission control onto the enemy. The first phase is survivable due to alien passivity, the second phase survivable because of the AI’s difficulty in capitalizing on their overwhelming advantages, and the third phase is just mopup.
List Of Suggestions
1) Rebalance mission control to be much less dependent on command centers and thus less prone to exponential growth.
2) Rebalance defensive fleets to cost much less MC, instead using limits on space mining to soft-cap fleet growth. Fleet battles to defend your mining infrastructure are impractical when fleets are expensive, static defenses are cheap, and the aliens willing to suicide one corvette at a time.
3) Leave Jupiter open for the player early game. If the enemy has superior strategic mobility, then dispersed asteroid-belt bases further drive the player towards static defense because their fleets just can’t be everywhere.
4) Rebalance research to be less exponential, in particular dealing with the absurdly high raw research/month output of research campuses and universities. In brief: Earth for raw research/month, space for percentage-based category bonuses.
5) Make the aliens much less comically inept at using their fleets, both strategically and tactically. This is probably the hardest to actually implement, but right now it is far too easy to neutralize alien fleets as a threat.
a. An interim patch would be to give alien warships more lasers and plasma, letting them actually kill something rather than just splash endless projectiles at a wall of point defense.
6) Give the aliens some progression in tech, infrastructure and strategy.Right now, they’re the equivalent of a “you must be this tall to ride the rollercoaster!” deal where the only question is how much infrastructure/research you need before provoking the aliens into open war.
7) Increase hydrogen mining output so it’s not so expensive to shuffle fission-powered warships around the solar system. Strategic mobility for human warships is currently pathetic until the advent of fusion drives.
a. Fission pulse and NSWR drives might compensate for this if they weren’t so expensive and so close to vastly superior fusion torches in the tech tree.
8) Make Earth scale better with tech, rather than ring habs almost completely obsoleting the mother planet.
Exponential Growth
Exponential growth is characterized by having something which feeds back on itself to double in constant time without limit. If you can use something to make more of the same thing at a fixed rate, you have yourself an exponential curve.
In Terra Invicta’s case, once ring stations are researched, this simple condition is almost satisfied, producing a near-exponential growth phase. I can build a ring station at Mercury with 14 command centers producing 23 net mission control. Some of this mission control is used up to support nanofacturing complexes to keep you cash-neutral, and some more is used to build space mines to support all this.
However, you’re still left with a lot of mission control, which can be used to build more MC rings and their attendant mines/nanofactories. Even if you’re only left with 5 MC per ring after subtracting out the nanofactories and mines, that means a doubling time of one year. Each existing MC ring lets you support one MC ring under construction, and at the end of the year, you now have twice as many MC rings to start construction on MC rings 3-4, etc.
It’s not quite perfect exponential growth, as mining bases are not all equally productive and Mercury only has so many orbital slots, but near-exponential growth lasts long enough to trivialize the endgame.
How Games Currently Play Out
Initially, the aliens dominate space, and the only reason the player isn’t immediately crushed is because alien hate is kept under control. The player builds up some mining habs until they reach the alien hate limit, at which point usually there’s a plateau as they wait for research to catch up without triggering a not-yet-winnable conflict with the aliens. Meanwhile, after their initial burst of hab construction in the outer solar system, the aliens are happy to just sit there and slowly build up fleet strength.
While the graph doesn’t show this, there is sometimes also a period of defensive conflict, where the player isn’t plateaued by the alien hate limit, but rather by the amount of MC they can build on Earth. This is usually a painfully slow grind as most of your CP is invested in nations which are already at their MC limit, slowing down your MC growth.
Then you get ring habs, and it’s basically all over for the aliens. You can go full von Neumann, with space resources powering nanofacturing complexes which fund command centers which support both research bases and more mining outposts. Within just a few years of ring habs, you’re out-producing the aliens, at parity and swiftly exceeding alien tech, and alien fleet control is still terrible.
A Tangent into Research: Earth for Raw Grunt, Space for Bonus Synergy
This is also the point where a few thousand scientists and engineers in space magically become vastly more productive than millions of scientists and engineers on Earth. A rich, well-educated, completely unified EU should not be eclipsed by two research campus rings at Mercury. While this will get somewhat more expensive once research campuses start costing mission control, this doesn’t change the fact that you can tap into some of that exponential growth of MC rings to instead send your research rate screaming upwards.
My preferred solution to this would be to eliminate research campuses and universities entirely, and instead orient space research around multiplicative bonuses, along with a reduction in cost of endgame technologies to compensate for the loss of exponential growth in raw research/month. Adding techs to boost Earthside research output can also help compensate for players losing their eight identical research campus rings orbiting Mercury.
As to Project Exodus, there are two solutions. The first is to force them into the dilemma of either keeping Earth or living with the trickle of raw research that the specialty institutes provide. The second is to give them a faction-specific project to let them build research campuses/universities. Otherwise, it just doesn’t fit with either realism or the Earth-centric philosophies of all the other factions.
I’d also suggest incentivizing player to build labs in places other than LEO. Unless I’m missing something, three T3 labs of each category in LEO max out category research bonuses and their bonus to Earthside IP priorities.There’s no benefit in sending geologists to Mars, chemists to Venus, particle physicists to Jupiter, etc: all science can be done either on Earth, in LEO, or in stations orbiting Mercury.
Adding bonuses for labs on diverse locations would also help keep up growth in research output. Turn the Galilean moons into forgeworlds? All well and good, but you’d be able to get more research if you also put down some labs at Saturn, Makemake and Venus.
Methods of Eliminating the Exponential Phase Transition
In addition to nuking research campuses/universities as above, there are several ways of softening out human growth in capabilities.
First, the command center deserves special attention for enabling exponential growth. I would boot it to a very late-game global tech. To partially compensate players for the loss of their exponential growth machine, several adjustments can be made.
Add some techs to improve Earthside mission control, both in the speed of building MC and in the amount of MC a single region can provide.
Increase the MC consumption of habs/stations, and vastly reduce the MC consumption of ships. Unless the aliens just sit on their hands for a couple decades and let you build 479 battleships to protect Earth, I see no problem with indirectly limiting human fleet growth by instead limiting human space economy. What I do see a problem with is how mining hab defense can be summed up as “slap a couple LDAs on it and let the aliens suicide a stream of corvettes against it.”
Ironically, the aliens do the “sit there and build an enormous number of warships” thing, and the only reason that’s not a problem is how ineptly the aliens use their warship doomstacks. Alien warships should be a threat, and right now they are not threatening. They suicide corvettes at LDA-protected isolated habs, and suicide doomstacks at 10 battleship/dreadnought point defense walls.
The next idea to permit more extensive defensive fleets (particularly before your drives are good enough to produce mobile defensive fleets) is to reduce MC upkeep for planetary systems with shipyards, command centers or both. If command centers are involved, you can still punt their +2 raw MC bonus to a late-game tech.
While less important, far too much is concentrated in the single global tech node of ring stations. Right now, it immediately provides expansion to five sectors, T3 labs, command centers, T3 hotels/geriatrics and T3 nanofacturing complexes. Agricultural complexes and solar/fusion farms should stay with the ring station global tech, as those are a near-requirement for making use of T3 rings.
Spaceworks, in addition to being made actually worthwhile compared to a pair of T2 shipyards, could be moved to improved shipbuilding techniques (the dreadnought/lancer global). Battlestations are in a similar place, of costing far too much for a meagre improvement over LDAs. Command centers have already been discussed for being wildly overpowered.
Allowing for 5-sector T2 orbitals/habs would give a midgame upgrade which feels like a worthwhile stepping stone between 3-sector T2 and 5-sector T3 stations. There are a few ways in which even T2 stations benefit from economy of scale in expanding to five sectors: you still only need 1-2 LDAs, refueling stops still only need 1 spacedock/supply depot, you still only need the same fraction-of-a-farm for the core, it takes up only one orbital/surface slot at the chosen celestial body, etc.
It would also solve a personal pet peeve of mine, that to get N labs/hotels in orbit, either I need to spam more T2 stations than I’ll want to keep, or I need to wait for ring stations.
Separating out some of the T3 buildings into new cheap global techs can help the player tune their progress to what it is they actually need most urgently: beeline T3 labs for more research, T3 hotels and nanofactories to stabilize cash flow, etc.
Overall, I would prioritize rebalancing mission control, making alien fleets [s]great againthey weren’t great to begin with[/s]threatening, then 5-sector T2 habs as an intermediate stepping stone, and then maybe breaking up the T3 buildings into new nodes.
The Missing Element: Alien Progression and Desperation: “We Might Actually Lose”
As I mentioned before, the aliens are basically asking kids if they’re tall enough to ride the rollercoaster. They’re far too static in the threat they pose, and don’t adapt very much to the humans.
First: give them some tech progression, especially their drive systems. This should help keep the alien threat dynamic, keep the aliens believable as they try to keep their tech advantage, and make tactics and strategy more believable. Right now, until you get fusion torches, alien strategic mobility helps enforce the sudden phase transition from passive defense to stomping all over anything alien-shaped.
Right now, in the early game, their fusion torches virtually require you to use cheese strategies when defending yourself. Human electric drives accelerate so slowly that your surface habs will die before intercept, and the fission drives have so little dV that they can just run away until you need to RTB and refuel your ships. The only viable defense is the pincer attack, exploiting the “still in battle” state to force the aliens to engage the second side of the pincer.
On the offensive, you currently tie up a very large, expensive fleet for a long time, often burning a lot of hydrogen on a one-way trip to an alien station. Meanwhile, a theoretically competent alien commander could intercept said fleet at his leisure. This is exacerbated by how the time in between “can contemplate building an offensive fleet” and “have fusion drives” is so short that your torchships might get there first.
If the aliens’ drive tech starts within shouting distance of humanity, then the behavior can be made much more realistic. If they come at your NERVA drives with the equivalent of grid drives, then they’re heavily committed to the attack: they don’t have the acceleration to run away once they get too close to a fission drive. If they come in with the equivalent of a Pegasus drive, they can run away once or twice, but if you’re willing to throw enough ships and enough hydrogen at the matter, they’ll be forced to either retreat or do battle… and then if you chase them with ion drives, you can still force a battle a few months into their retreat.
On the offensive, then, you’re on the other side of that coin, and you better pray you brought enough ships, because your ion-drive warships are outdone by their grid drives, and your NERVAs are outdone by their Pegasus drives. You can force a defensive engagement or retreat with superior numbers, they can force the same just by having moderately more mobility.
In terms of realism, this can also help, because right now it appears that the aliens are technologically stagnant and won’t respond at all when they realize “hey, we might actually lose”. They can start to push out their own research and then start to just outright steal human technology if they start to fall behind.
Another side of that is infrastructure and strategy: an increasingly desperate Hydra administration can be made much more responsive. They can expand the wormhole, and more crucially, start to economize on their exotics usage. They can look at diamondoid-protected human warships starting to nip at their bases and think “Maybe we should start building our own diamondoid warships: while we’ll lose some tech advantage, we need good enough now, not perfect once they’re preparing an assault on the wormhole.” They can start to think “maybe a half-dozen mining outposts isn’t enough: we need to expand out even if it means committing more Hydras to the Earth operation.”
A component of Terra Invicta’s story is that the Hydras came in complacent, expecting to use a minimum of resources to take over Earth. A problem of the gameplay is that the Hydras seem to stay complacent, at most ramping up their shipbuilding, something mostly lost on players who are able to trivialize the threat of alien warships.
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Abstract
Current game balance and progression in Terra Invicta is dominated by two major factors: poor alien AI and an exponential increase in mission control availability once command centers are unlocked. The first makes the aliens feel unsatisfying as an opponent, and exponential growth in player capabilities throws any difficulty out the window once the exponential loop gets going. After you are able to put down significant numbers of command centers, the first endgame is a victory march, and subsequent endgames are boring slogs to polish off aliens who don’t yet realize the situation is hopeless.
Introduction
As I understand things, mission control and alien hate were introduced to keep players from going von Neumann (i.e.exponential growth) and trivializing the game.
However, as implemented, this merely delays the transition to exponential growth, thus putting all the difficulty into surviving up until a sharp transition to overwhelming power, a point shortly after researching command centers.
Exacerbating this is the combination of nominally overwhelming alien power and the sheer ineptitude with which that power is wasted by the AI. The aliens may outnumber your ships 10:1 with a major tech advantage, but that doesn’t matter if they send out penny packets to be dismembered by hab defenses and the occasional fleet to be destroyed by player point defense walls. The flipside is that if the aliens were made competent without any other changes, it would be extremely difficult or impossible for the player to win because of that overwhelming technological and infrastructure advantage.
Furthermore, the player is limited by a combination of limited mission control and inefficient drives during the early game, favoring passive gameplay until command centers alleviate MC limitations and space research swiftly clears out the tech tree. It is very difficult to spare the hydrogen and mission control for a mobile campaign, and easy to instead let the alien ships suicide themselves against static hab defenses and your Earth defensive fleet.
This leads to three phases of gameplay: a passive phase where you build your initial infrastructure, a defensive phase where you exploit AI weaknesses to preserve your infrastructure, then once command centers are available, an offensive phase where the player just tips a gigantic pile of research, space resources and mission control onto the enemy. The first phase is survivable due to alien passivity, the second phase survivable because of the AI’s difficulty in capitalizing on their overwhelming advantages, and the third phase is just mopup.
List Of Suggestions
1) Rebalance mission control to be much less dependent on command centers and thus less prone to exponential growth.
2) Rebalance defensive fleets to cost much less MC, instead using limits on space mining to soft-cap fleet growth. Fleet battles to defend your mining infrastructure are impractical when fleets are expensive, static defenses are cheap, and the aliens willing to suicide one corvette at a time.
3) Leave Jupiter open for the player early game. If the enemy has superior strategic mobility, then dispersed asteroid-belt bases further drive the player towards static defense because their fleets just can’t be everywhere.
4) Rebalance research to be less exponential, in particular dealing with the absurdly high raw research/month output of research campuses and universities. In brief: Earth for raw research/month, space for percentage-based category bonuses.
5) Make the aliens much less comically inept at using their fleets, both strategically and tactically. This is probably the hardest to actually implement, but right now it is far too easy to neutralize alien fleets as a threat.
a. An interim patch would be to give alien warships more lasers and plasma, letting them actually kill something rather than just splash endless projectiles at a wall of point defense.
6) Give the aliens some progression in tech, infrastructure and strategy.Right now, they’re the equivalent of a “you must be this tall to ride the rollercoaster!” deal where the only question is how much infrastructure/research you need before provoking the aliens into open war.
7) Increase hydrogen mining output so it’s not so expensive to shuffle fission-powered warships around the solar system. Strategic mobility for human warships is currently pathetic until the advent of fusion drives.
a. Fission pulse and NSWR drives might compensate for this if they weren’t so expensive and so close to vastly superior fusion torches in the tech tree.
8) Make Earth scale better with tech, rather than ring habs almost completely obsoleting the mother planet.
Exponential Growth
Exponential growth is characterized by having something which feeds back on itself to double in constant time without limit. If you can use something to make more of the same thing at a fixed rate, you have yourself an exponential curve.
In Terra Invicta’s case, once ring stations are researched, this simple condition is almost satisfied, producing a near-exponential growth phase. I can build a ring station at Mercury with 14 command centers producing 23 net mission control. Some of this mission control is used up to support nanofacturing complexes to keep you cash-neutral, and some more is used to build space mines to support all this.
However, you’re still left with a lot of mission control, which can be used to build more MC rings and their attendant mines/nanofactories. Even if you’re only left with 5 MC per ring after subtracting out the nanofactories and mines, that means a doubling time of one year. Each existing MC ring lets you support one MC ring under construction, and at the end of the year, you now have twice as many MC rings to start construction on MC rings 3-4, etc.
It’s not quite perfect exponential growth, as mining bases are not all equally productive and Mercury only has so many orbital slots, but near-exponential growth lasts long enough to trivialize the endgame.
How Games Currently Play Out
Initially, the aliens dominate space, and the only reason the player isn’t immediately crushed is because alien hate is kept under control. The player builds up some mining habs until they reach the alien hate limit, at which point usually there’s a plateau as they wait for research to catch up without triggering a not-yet-winnable conflict with the aliens. Meanwhile, after their initial burst of hab construction in the outer solar system, the aliens are happy to just sit there and slowly build up fleet strength.
While the graph doesn’t show this, there is sometimes also a period of defensive conflict, where the player isn’t plateaued by the alien hate limit, but rather by the amount of MC they can build on Earth. This is usually a painfully slow grind as most of your CP is invested in nations which are already at their MC limit, slowing down your MC growth.
Then you get ring habs, and it’s basically all over for the aliens. You can go full von Neumann, with space resources powering nanofacturing complexes which fund command centers which support both research bases and more mining outposts. Within just a few years of ring habs, you’re out-producing the aliens, at parity and swiftly exceeding alien tech, and alien fleet control is still terrible.
A Tangent into Research: Earth for Raw Grunt, Space for Bonus Synergy
This is also the point where a few thousand scientists and engineers in space magically become vastly more productive than millions of scientists and engineers on Earth. A rich, well-educated, completely unified EU should not be eclipsed by two research campus rings at Mercury. While this will get somewhat more expensive once research campuses start costing mission control, this doesn’t change the fact that you can tap into some of that exponential growth of MC rings to instead send your research rate screaming upwards.
My preferred solution to this would be to eliminate research campuses and universities entirely, and instead orient space research around multiplicative bonuses, along with a reduction in cost of endgame technologies to compensate for the loss of exponential growth in raw research/month. Adding techs to boost Earthside research output can also help compensate for players losing their eight identical research campus rings orbiting Mercury.
As to Project Exodus, there are two solutions. The first is to force them into the dilemma of either keeping Earth or living with the trickle of raw research that the specialty institutes provide. The second is to give them a faction-specific project to let them build research campuses/universities. Otherwise, it just doesn’t fit with either realism or the Earth-centric philosophies of all the other factions.
I’d also suggest incentivizing player to build labs in places other than LEO. Unless I’m missing something, three T3 labs of each category in LEO max out category research bonuses and their bonus to Earthside IP priorities.There’s no benefit in sending geologists to Mars, chemists to Venus, particle physicists to Jupiter, etc: all science can be done either on Earth, in LEO, or in stations orbiting Mercury.
Adding bonuses for labs on diverse locations would also help keep up growth in research output. Turn the Galilean moons into forgeworlds? All well and good, but you’d be able to get more research if you also put down some labs at Saturn, Makemake and Venus.
Methods of Eliminating the Exponential Phase Transition
In addition to nuking research campuses/universities as above, there are several ways of softening out human growth in capabilities.
First, the command center deserves special attention for enabling exponential growth. I would boot it to a very late-game global tech. To partially compensate players for the loss of their exponential growth machine, several adjustments can be made.
Add some techs to improve Earthside mission control, both in the speed of building MC and in the amount of MC a single region can provide.
Increase the MC consumption of habs/stations, and vastly reduce the MC consumption of ships. Unless the aliens just sit on their hands for a couple decades and let you build 479 battleships to protect Earth, I see no problem with indirectly limiting human fleet growth by instead limiting human space economy. What I do see a problem with is how mining hab defense can be summed up as “slap a couple LDAs on it and let the aliens suicide a stream of corvettes against it.”
Ironically, the aliens do the “sit there and build an enormous number of warships” thing, and the only reason that’s not a problem is how ineptly the aliens use their warship doomstacks. Alien warships should be a threat, and right now they are not threatening. They suicide corvettes at LDA-protected isolated habs, and suicide doomstacks at 10 battleship/dreadnought point defense walls.
The next idea to permit more extensive defensive fleets (particularly before your drives are good enough to produce mobile defensive fleets) is to reduce MC upkeep for planetary systems with shipyards, command centers or both. If command centers are involved, you can still punt their +2 raw MC bonus to a late-game tech.
While less important, far too much is concentrated in the single global tech node of ring stations. Right now, it immediately provides expansion to five sectors, T3 labs, command centers, T3 hotels/geriatrics and T3 nanofacturing complexes. Agricultural complexes and solar/fusion farms should stay with the ring station global tech, as those are a near-requirement for making use of T3 rings.
Spaceworks, in addition to being made actually worthwhile compared to a pair of T2 shipyards, could be moved to improved shipbuilding techniques (the dreadnought/lancer global). Battlestations are in a similar place, of costing far too much for a meagre improvement over LDAs. Command centers have already been discussed for being wildly overpowered.
Allowing for 5-sector T2 orbitals/habs would give a midgame upgrade which feels like a worthwhile stepping stone between 3-sector T2 and 5-sector T3 stations. There are a few ways in which even T2 stations benefit from economy of scale in expanding to five sectors: you still only need 1-2 LDAs, refueling stops still only need 1 spacedock/supply depot, you still only need the same fraction-of-a-farm for the core, it takes up only one orbital/surface slot at the chosen celestial body, etc.
It would also solve a personal pet peeve of mine, that to get N labs/hotels in orbit, either I need to spam more T2 stations than I’ll want to keep, or I need to wait for ring stations.
Separating out some of the T3 buildings into new cheap global techs can help the player tune their progress to what it is they actually need most urgently: beeline T3 labs for more research, T3 hotels and nanofactories to stabilize cash flow, etc.
Overall, I would prioritize rebalancing mission control, making alien fleets [s]great againthey weren’t great to begin with[/s]threatening, then 5-sector T2 habs as an intermediate stepping stone, and then maybe breaking up the T3 buildings into new nodes.
The Missing Element: Alien Progression and Desperation: “We Might Actually Lose”
As I mentioned before, the aliens are basically asking kids if they’re tall enough to ride the rollercoaster. They’re far too static in the threat they pose, and don’t adapt very much to the humans.
First: give them some tech progression, especially their drive systems. This should help keep the alien threat dynamic, keep the aliens believable as they try to keep their tech advantage, and make tactics and strategy more believable. Right now, until you get fusion torches, alien strategic mobility helps enforce the sudden phase transition from passive defense to stomping all over anything alien-shaped.
Right now, in the early game, their fusion torches virtually require you to use cheese strategies when defending yourself. Human electric drives accelerate so slowly that your surface habs will die before intercept, and the fission drives have so little dV that they can just run away until you need to RTB and refuel your ships. The only viable defense is the pincer attack, exploiting the “still in battle” state to force the aliens to engage the second side of the pincer.
On the offensive, you currently tie up a very large, expensive fleet for a long time, often burning a lot of hydrogen on a one-way trip to an alien station. Meanwhile, a theoretically competent alien commander could intercept said fleet at his leisure. This is exacerbated by how the time in between “can contemplate building an offensive fleet” and “have fusion drives” is so short that your torchships might get there first.
If the aliens’ drive tech starts within shouting distance of humanity, then the behavior can be made much more realistic. If they come at your NERVA drives with the equivalent of grid drives, then they’re heavily committed to the attack: they don’t have the acceleration to run away once they get too close to a fission drive. If they come in with the equivalent of a Pegasus drive, they can run away once or twice, but if you’re willing to throw enough ships and enough hydrogen at the matter, they’ll be forced to either retreat or do battle… and then if you chase them with ion drives, you can still force a battle a few months into their retreat.
On the offensive, then, you’re on the other side of that coin, and you better pray you brought enough ships, because your ion-drive warships are outdone by their grid drives, and your NERVAs are outdone by their Pegasus drives. You can force a defensive engagement or retreat with superior numbers, they can force the same just by having moderately more mobility.
In terms of realism, this can also help, because right now it appears that the aliens are technologically stagnant and won’t respond at all when they realize “hey, we might actually lose”. They can start to push out their own research and then start to just outright steal human technology if they start to fall behind.
Another side of that is infrastructure and strategy: an increasingly desperate Hydra administration can be made much more responsive. They can expand the wormhole, and more crucially, start to economize on their exotics usage. They can look at diamondoid-protected human warships starting to nip at their bases and think “Maybe we should start building our own diamondoid warships: while we’ll lose some tech advantage, we need good enough now, not perfect once they’re preparing an assault on the wormhole.” They can start to think “maybe a half-dozen mining outposts isn’t enough: we need to expand out even if it means committing more Hydras to the Earth operation.”
A component of Terra Invicta’s story is that the Hydras came in complacent, expecting to use a minimum of resources to take over Earth. A problem of the gameplay is that the Hydras seem to stay complacent, at most ramping up their shipbuilding, something mostly lost on players who are able to trivialize the threat of alien warships.