Entrance condition:

{
  "comeInJumping": {
    "speedBooster": "any",
    "minTiles": 1
  }
}

Requires:

"canCrossRoomJumpIntoWater"
{
  "useFlashSuit": {}
}
{
  "shinespark": {
    "frames": 10,
    "excessFrames": 5
  }
}
{
  "enemyDamage": {
    "enemy": "Cacatac",
    "type": "spike",
    "hits": 1
  }
}

Dev note: The spike hit may be avoidable, but it shouldn't matter much. The runway could be reduced to 0.4375 tiles with SpeedBooster.