Enter the room while building a shinespark and use it on the lowest part of the ramp to cross the room and reach a raised ledge on the right side wall. From there, use SpaceJump to escape the water. Carry the shinespark to the bottom of the ramp by delaying the first Choot with two Power Beam shots, killing it, or bounceballing through it. The Choot can be shot diagonally from the middle platform, and again by running off that platform and aiming down to float above it.

Entrance condition:

{
  "comeInShinecharging": {
    "length": 6,
    "openEnd": 1,
    "steepDownTiles": 1
  }
}

Requires:

"canShinechargeMovementComplex"
"canCarefulJump"
{
  "or": [
    {
      "and": [
        "canMidairShinespark",
        "canDodgeWhileShooting"
      ]
    },
    {
      "and": [
        {
          "enemyDamage": {
            "enemy": "Choot",
            "type": "contact",
            "hits": 1
          }
        },
        "canNeutralDamageBoost",
        "canBounceBall"
      ]
    },
    {
      "and": [
        "canMockball",
        {
          "or": [
            "canPseudoScrew",
            "ScrewAttack",
            "Plasma",
            "Wave",
            {
              "ammo": {
                "type": "Missile",
                "count": 1
              }
            },
            {
              "ammo": {
                "type": "Super",
                "count": 1
              }
            }
          ]
        }
      ]
    }
  ]
}
"canHorizontalShinespark"
{
  "shinespark": {
    "frames": 123,
    "excessFrames": 5
  }
}
"canSpaceJumpWaterBounce"
{
  "or": [
    {
      "and": [
        "HiJump",
        "canSpaceJumpWaterEscape"
      ]
    },
    {
      "and": [
        "canTrickyJump",
        "canDownGrab"
      ]
    },
    "canWalljump"
  ]
}