cool game, thank you!
there is a minor confusion with Assasin's description, saying that it attacks when an ally "in front attacks". first, it was unclear if this meant the ally in the front of the line or directly in front of the Assasin, and second there are units that can "attack" from any rank like Bowie and Stoner, but they don't trigger Assasin's attack unless they engage in melee combat. so i think it'd be better if Assasin attacked together with the unit in front of it, no matter which rank they are in
overall, such a high quality game, although very small. gives major plants vs zombies vibes and can be a huge success if you make an extended 40-60 min version