The most important issue to address when looking at this game is what meta you want the game to have. With this in mind I'm outlining the cards and their effects on the game as a whole.

Retrofit allows you to avoid a turn 2 OTK, obviously that's a good thing. Other than that, it's situationally useful at best but since it's 0 cost there's no reason to not play it. I'd run 2 in every deck, since OTKs are a thing.

Gambit introduces some insane card draw to the game, this is the card that enables miracle turns and complete nonsense to happen, I consider this a good thing.

Siege is incredibly useful as a combo piece. If you get this and curse on turn one you just won the game pretty much. The opponent's best case scenario is that they lose half their men on turn 2. If you get this card, any one cost building, demolish, gambit and wisdom, you can OTK on turn 2. Since there's so much counterplay to that and since it requires a huge luck level, I don't consider it a problem, but it's definitely something to consider.

Revolt is the card you run in every stall deck, and maybe run in your aggro deck.

Abbey is the card you run if you need man generation, which generally speaking you do.

Temple is one of those cards that is OP in certain situations but in every other situation is a target for gambit.

Call to Arms is what you always run in your aggro deck as a counter to revolt.

Wisdom is a card that is really good verging on overpowered in aggro decks but might be outclassed in some others. That being said I'd still consider running at least one of these in pretty much every deck I make. The game's most useful cards are pretty much all tier two. Wisdom on its own might be a good card, but I think mainly the combination of this card with a few others is the real problem.

Pillage is a hard counter to people running AI on especially problematic sites... and it can be useful early game as a counter to people using shrine or something to get a crazy site early. I'd say it's balanced. Run these in your aggro deck to prevent stall from force field.

Plague is the card you want to run two of to force your opponent to waste AP relocating men.

Fortify would be useful if sites had more health but as it stands you're better off spending 1 AP on a new site entirely 90% of the time. You're better off running two 1 cost sites instead of Fortify. You could target the homeland, which is something I guess.

Curse is straight up overpowered for a lot of reasons. If you play it turn one, your opponent is forced to move all their men off the homeland - their most valuable site at the start of the game. Even late game this can bring the game to a grinding halt. If my opponent and I didn't agree to stop using this card entirely, we both would have needed to run the card at 2 just to put the same level of stress on each other. The fact that this card enables more OTK possibilities is also cause  for alarm. This should be either a 3 cost level 2 card or a 2 cost level 3 card. The fact the target site stays cursed after the effect happens, it's just completely bananas.

Shrine is incredibly situationally useful. This card has allowed me to cheese my way to victory on more than one occasion. Can be overpowered early game but I'd argue it's less OP than Factory for sure.

Church is the second worst site. Consider first the counters to church: Revolt, Siege, and Plague are all 1 costs. Plague completely bricks it. Siege leaves it open to a catapult kill. Revolt is the best case scenario, but by then you're losing 2 men at best. AI isn't even good with it because the church is 2 cost, even if it was 1 cost plague can still brick it. Next, consider the fact that you pay 2 AP to summon it, and 1 AP to move men to it, wasting an early game turn that could be used to immediately get 2 men on an abbey site and either force removal from opponent or get more out of it than you would out of church OR you could be running Fort which is the same cost but immediately nets you 3 men which is much more valuable for most decks. This card at the very least should be one cost. I'd change the effect cost to just be 2 men, or immediately make it come into play with 1 man. Or keep it the same and make it generate 2 men a turn.

Fort is a card that I wouldn't really do anything to change.

Railway is underwhelming. Needs a lot in order to work properly, your investment is completely destroyed if they have a siege in their hand. I'd just increase it's health by 1. Otherwise it's decent.

Backup is better than fort assuming you're level 2 but both have their niche. I don't think it's worth changing.

Sniper Nest is really, really situational. I'd say make it cost only 2 men to operate. Other than that a decent card that's hard countered by forcefield.

Factory is very overpowered. Most sites don't cost 3 AP, and since gambit exists you can reasonably cycle through a fair chunk of your deck in one turn. If the deck size were bigger, or if this card were 3 cost, this card wouldn't be as bad.

Mortar is only really useful in AI decks but when it's in an AI deck it's balanced well. Might change AP cost to 1 instead of 2 but then it might be imbalanced.

Library, Lab, and Military Base are all balanced well.

Bombing is a less flexable Revolt in most circumstances but might fit in an aggro deck well enough to run 2 of.

Hospital is balanced well.

Disarm is completely insane. I've won games because of just this card and locking their board to a state where they can't do damage fast enough to KO me. The cost of this card needs to increase.

AI is balanced, but a little underwhelming in most circumstances; I feel like if you changed it, it would be overpowered.

Demolish is pretty insane paired with Siege but is otherwise situational. I feel like I wouldn't change this card.

Supply Depot could be useful in incredibly rare situations to the point where I would say you shouldn't run it in any deck. The only deck I'd even consider running it in is a stall AI deck. Most of the time though so much site removal exists with no true counter that it's a crap shoot at best. At least it doesn't cost AP to repair a site. If this had 1 more health it would be great.

Trial is far, far too RNG dependent to be run most decks but I could see it having it's place in a miracle type deck. If you draw into Gambit it could be a game winning move, and most other cards in that deck are just immediately useful. Otherwise it's a fun card and wouldn't change it at all.

Radio Tower is absurdly useless. You could be running literally any other card in place of this one and be better off. 3 men and 1 AP cost means to use the effect of this card on the turn that you play it you have to use up 3 AP. 2 AP if you have Factory up and your opponent wasn't smart enough to remove it. This card could be useful if it stole all the men from a site, or if it was a level 1 card and didn't cost AP. As it stands it's an even worse church.

Force Field is a card with some insane variance depending on your opponent's hand. It's appropriately balanced, I would say. However, I could see it becoming overpowered or underpowered if the combo pieces are nerfed or the deck size is increased.

Clone is one of those cards that I'd run if it were level 2, if site health were buffed, or if Call to Arms wasn't better in almost every situation where you'd want to use this.

Missle Silo is a card I could see being used if it were more viable to stall out the game. It would be balanced. It's alright with AI, but not really all that great. As it stands I might run one. Also missile is spelled wrong. Don't know how to correct spelling without sounding rude. Sorry.

Shell Shock is kind of balanced, I think. It's really powerful, but since it's a 2 cost level 3 spell it works out alright. Its only real problem is that there is no counterplay available and there's already a ton of removal options. If you made Fortify increase a site's health by one as well as heal it, it'd be more balanced. But this card as it stands isn't a disaster.

Hi-Tech is more useful than I initially thought but it's not the best card out there. It's a fun card.

Atlantis is useful when you're on the ropes but otherwise not terribly so. I'd say it's a balanced card when used that way and less balanced when used with factory or shrine and temple.

Mirage is a card which could in theory be good but in practice almost never is. Make this a two cost.

Doom is outclassed by it's younger brothers. It desperately needs a buff, this card is a finisher so having it do 3 damage to every building isn't unreasonable I feel, since it requires a great deal of setup.

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If this game were more popular, my estimation of the "meta" decks would be as follows (in order of powerlevel):

An Aggro deck that focuses on OTKs using siege, demolish combos
A Miracle type deck that focuses on control and setting up a strong board state
A Stall deck that focuses on control and specifically locking opponent's board state in order to set up and pop off

Then there's a huge power gap between that and these two:

A midrange deck
any AI central deck

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I'm of the belief that the most fun decks are the combo-orientated decks. OTK as it stands has a few counters (one of them being another OTK deck going first), to the point where I think it makes sense to keep it as an archetype. Giving a few low-cost sites some more health would help the game in the long-term I feel to maybe help balance this some more. Control definitely needs to be nerfed because the combination of disarm and curse makes them overpowered as hell, but they should also be given more options to make up for it. The actual card makeup of the three most powerful current decks is also very similar. Some of the balancing suggestions I made might diversify the decklist a bit. In addition, I've thought up some new cards that might also help.

The next major problem is the most infuriating one in the game. It's entirely possible as it stands to get only bad draws and brick yourself as a result, if you have a decent amount of tier 3s in your deck. This does push for a faster meta but decreases build variety by quite a bit. I suggest the ability to discard 2 cards from your hand per turn, at no cost to you.



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Some new units and spells that might be good:

Refinery - 1AP 2HP Lvl1 - At the start of your turn, gain 1 AP.

Obelisk - 1AP 1HP Lvl3 - 1 man > your next spell does 1 more damage

Guardhouse - 1AP 2HP Lvl2 - 2 men > Allied buildings can't be targeted next turn

Witch Hut - 1AP 1HP Lvl1 - Gain a man and +1 life every time a spell is cast

Funhouse - 1AP 3HP Lvl2 - 1 man > reshuffle a card into your deck, draw a card

Mill - 2AP 4HP Lvl2 - 2 men + 1AP > destroy the top card of your opponent's deck

Observatory - 1AP 2HP Lvl2 - 2 men > look at the top card of your deck

Nuclear Plant - 2AP 5HP Lvl2 - Gain 1 AP a turn, when destroyed do 2 damage to your sites.

Wizard Tower - 5AP 4HP Lvl3 - Your spells cost 4 less AP.

Shiftscape - 1AP Lvl2 - Move a site from your side of the field to your opponent's

Stop - 1AP Lvl1 - Target cannot use its ability for a turn

Fidget Spinner - 0AP Lvl1 - Does nothing

Gift Exchange - 1AP Lvl2 - Each player picks a card from their hand and then they exchange cards

Plagiarism - 1AP Lvl2 - Shuffle two copies of a target site into your deck

Masonry - 1AP Lvl2 - Give a site +3 life

Genesis - 2AP Lvl3 - Give a site 8 men if 2 are present

Refresh - 3AP Lvl3 - Destroy a target and re-play it

Dark Pact - 1AP Lvl2 - Target site can't be targeted, but loses 3HP at the start of your turn

Supercomputer - 4AP Lvl3 - Target site doesn't need men to use its ability, ability  is used twice

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All in all it's a really fun game. Really like the different strategies, and I think all it needs is a little balance.