It's overall very well done, but I ended up by myself, as most testers would, and it becomes impossible to do anything. Maybe if there was scaling for the number of players, it would work well, but by yourself, it is near impossible, and 3 waves is too short for even if there were more players or just bots added in if needed. I like how every creature has its own abilities.
Lastly, when I went to play as the bee, the first bird just never spawned, staying in round 1, which I assume was a glitch.