Seems to happen with all special abilities. You should consider making the special abilities be a part of the board rather than being, seemingly, associated with an individual enemy if eliminating the enemy has no impact on the continued usage of the special ability.
I almost never comment on games. Good design, fun gameplay, interesting edge cases for balance (shields -> single target dmg + win init, damage soakers -> 2+ multi target large damage win init, damage reflection not redirected to tanks etc). However I have to say I am not surprised when I hear people saying that they've lost data. While the "stuck" or "invisible" bug can easily be fixed by saving and going to the lobby. I have thus far been unable to determine by what mechanism the incredibly broken swapping mechanism uses. Rarely can you actually swap a minion into an open slot, and often the slot it looks like you're selecting isn't the slot the minion goes to. many slots aren't selectable which leads to these cases where you cannot equip a 5th minion or sometimes a 4th if you're leveling minions later in the game to compare them. 1 star for shear frustration.
Zakana doesn't benefit from range boost.
This seems to be a very persistent problem across many different units. Someone else has mentioned assassin , but I've seen it now in zakana and scorpions. Either the range indicator doesn't mean the range of attack (which seems silly as for the towers with holes in the middle of their range ostensibly is indicated by that ring).
This should either be clarified as to what specifically that range boost applies to and what precisely that range indicator circle actually means. And more specifically why the bullets of some towers do not extend in range despite the tower showing increased range under the "range aura" tab as well as with the radius increase of the range circle.
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