One method to kill the crabs is to wait on the central platform until a crab comes near, then move with it laying bombs in its path. Another is to wait in the doorway and place three bombs to hit it while bouncing over it. The top of the IBJ will be off camera. Starting the IBJ as far to either side as possible and holding forward once off camera will make it easier to get through the morph tunnel.

Entrance condition:

{
  "comeInWithGMode": {
    "mode": "any",
    "morphed": true
  }
}

Requires:

"Gravity"
"h_canArtificialMorphIBJ"