There is a bug where if you die to a stalker during the transition from Forest 2 to the final boss then you get teleported back to Forest 2 blister and then into the boss fight (I thought this was a secret until I died after popping the blister and then realizing it's a save state).
Also secondly, does anyone know how to get the "grab a pearl" achievement? The van song mentions destroying a pearl and walking on the ocean but I don't know if that's connected