Only requires a runway of one tile in the adjacent room. Bomb boost through the doorway, then use spring ball to get to the bottom left ledge. To avoid hitting the Skultera, place the bomb a few pixels from the doorway. One way to setup the positioning of the bomb is to place it, unmorph, rotate, and remorph

Entrance condition:

{
  "comeInWithBombBoost": {}
}

Requires:

"canSpringBallBombJump"
"canCrossRoomJumpIntoWater"
{
  "or": [
    "Gravity",
    "HiJump",
    "canSpringBallJumpMidAir",
    "h_canCrouchJumpDownGrab"
  ]
}