Great game!
Only three main criticism's are:
1) Selena is overpowered. Absolutely no reason not to use her.
2) Story and dialogue was pretty cringe-y or pointless.
3) It felt off-putting that some of the upgrades were entirely leader-dependent.
Aside from that though, fun game. I think a good idea would be to cut the recharge of super abilities by 2/3, but make it so you can switch the leader at any time while playing. This makes it so the player has multiple abilities to juggle and the passives can be made use of when required (such as switching to the engineer when he's low on life in order to save him).
A cool feature would be if you could change the order of your army in-between waves (like say, if you have two turtles, you can keep switching one out to the front while the other heals up in the middle, or you could move your healers about etc...). It would create more strategy and decision making. Perhaps left for a sequel, though.
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