It took me a minute to understand the enemy tanks will all shoot 1 turn before mine, and the 2 barrels tank was not obvious at first (I understood quickly after, but in a game like this, it should be immediate I guess).
But other than that, a good little puzzle game, it was pretty fun and the art goes well with the design.
Perhaps the level design should be slightly more open, to allow a little bit more freedom of movement ? Even if it's part of the puzzle to figure out the best movement options, it felt a little bit too restrictive.