In the latest snapshot, new fish mobs we added/updated. The pufferfish became a mob, with its own abilities and hitbox. The pufferfish can poison you if you get too close, but wouldn't you think by get too close, it means, have your hitbox collide with its? The pufferfish gives you poison from a distance that a zombie could hit you at, but whenever you are in that range, you are instantly attacked. That is not how pufferfish should work, because there is no clear indicator of how close you should get, and unlike zombies, they are not viewed as hostile, just defensive. Their poison range is so big that you could just swim past, not even notice they're there, and then get poisoned. I feel like this should be fixed very soon in a future snapshot, because rather than making the ocean interesting, this could make the ocean annoying.