What about creating a kind of training fights, which won't give any loot or exp, but also won't cost energy and won't decrease items durability? Just for having some fun while waiting for the energy to restore.
Adding some buffs/debuffs for both towers and enemies would give a lot to the battles. They don't have to be something extraordinary - good old poisoning, freezing, burning, breaking armour, fast regeneration, chain hit etc. would do. But there are only stun and area stun for knights an tors - that's not enough.
The battles lack for tactical depths: the upgrades for all towers are the same and not really creative with plain doubling and without different upgrade paths, Tor makes other melee units excessive, the enemies don't differ from each other much (a bit more speed, health, armour - but no special skills. Only Flight contributes something to tactics making you buy archers).
I don't say it's a bad game, but some other TDs (for Example "Kingdom rush", which has a very similar mechanics) are far superior to it.
I've customized controls with S - Slide, D - dagger and F - Parachute (Flight). It's way easier for me to notice them when the key gives a direct association with the action.
All the resistance/weakness thingie is a bit weird. Why can a spirit be frozen? Why can a stone golem be burning? Why can a sceleton be stunned? etc. Battle tacticks sucks, because a unit from any row can attack an enemy from any row. That way melee and ranged are no different, there can be no tanks etc.
I do like the game mechanics - it makes deck building interesting and battles tactically deep. I do appreciate multiplayer: both duels and live play. But I'm tired of all the grinding. Fighting the same or very similar enemies again and again, fighting in pvp with an almost static deck. All because you need an eternity to farm enough gems for a new booster or EVOs.
The map generator gets stuck sometimes - after several runs I start every time with the very same map and the power-ups at the same places for the first seconds of the race. And when such a thing happens I have to refresh the game - quitting to main menu doesn't help, I still get the same starting map every time I play. Is that a bug or a feature?;)
When I'm under lvl 3 I can play again after a crash by pressing Enter. After unlocking the abilities it's not working anymore - I have to use the mouse. Please, improve that.
I've completed the game before the badges appeared, but it won't give them to no. I do like the game, but it's a bit annoying, that I have to do all the levels all over again.
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It's actually by design that you see the same set of buildings - the game will generate a new world each day.