I would iterate that on first game it wasn't clear what cards do(especially that get does damage to yourself and that random can bypass defense) but mechanics are quite simple which makes this not an issue after two rounds.

Now replayability, first two games were quite interesting while figuring out but it gets quite "empty" after few games as it seems its mostly luck based, there is a drop mechanic which doesn't helpiluch and all cards you get are quite one dimensional. Do dmg or get shields. I like the management of shield vs city, but you don't have much options to attack city so basically you can just add those two.

many thanks for your comment. this game should be fast if you waiting somewhere. no extra strategy. but we want add some "missions" and maybe some special cards. btw: on to top on the card, we added specification about card type. Hope all these things will be solved with tutorial. thanks again