Pretty good, but boring. Couldn't even make it to the boss. I like the "countdown to boss" counter in the top, but with only two (very similar) enemy types, and no changes in patterns or waves, it's way too long. Basically, it needs more stuff, and less waiting.
EDIT: I hope there's not some really cool mechanic that you can only do while playing two-player. I really like those kinds of thing, but there's no indication that this is a multiplayer-only game, and several indications that it isn't. Therefore, it should either be fun single-player, or indicate that it is multiplayer-only.
Viewing post in ifman1 UNION jam comments
HAH! Great feedback. I went back and forth on how long to make the level before the boss comes out. Yes, there is a special ability that only appears during a 2 player game, but you have to make it to the boss in order to use it. Will I get disqualified for shortening the countdown for the purposes of this JAM? Instead of 9000 km I can put the boss at 3600 km so you guys can see the boss and the cool "Union" mechanic after 2 minutes instead of 5... but you have to kill a lot of enemies in order to use the Union, that's energy at the bottom of the screen, not a score.