The red area is the immunity zone. It prevents the crabification described in the credits area, and is full of talking crabs the purple is the rift to go to sea space and even further to the super octopus dimension. here is some multiverse info
warning: If outside the red zone/safe zone of this dimension, you will gradually turn into a crab. It takes 5 days to fully become da crab (or you can press magic button that does it instantly) or any other crustacean, if you choose to be in there for 15 more days, your permanently a crab (you keep your powers but your just a normal sized crab). You are still able to leave, but you're permanently a crab. If you leave before that, it will take 1 days to become normal.
