This was pretty fun! And as someone who also programmed 2d waves, I appreciate the effort involved.
Three things to consider improving: (1) Jumping the boats is a lot of fun; probably the best part of the game. You should get bonus points or a speed-boost for doing it. (2) If the AI dies from a shark, they should respawn. Having the game end because the AI is dumb doesn't feel great. (3) It's possible to get stuck on the boats. Maybe the dolphin needs a way to flop/jump off.
Thank you for the review!
Jumping gives a speed boost. I hadn’t considered giving an extra bonus speed when jumping over boats, that’s a good idea. The game was originally planned as an endless runner and later evolved into a race game, so there might be a bit of a weird mix of design mechanics. For example, getting stuck after a bad jump is partly intentional. I could fix it easily by tweaking the physics material, but then even a bad jump could end up being beneficial. Maybe letting the player make tiny jumps out of the water could fix it.
