12

Run right-to-left to gain a shinecharge on the upper right ledge. Use a gravity jump, Space Jump, or HiJump to approach the door above and spark out.

Requires:

"Gravity"
{
  "or": [
    "SpaceJump",
    "canGravityJump",
    {
      "and": [
        "HiJump",
        {
          "or": [
            "canWalljump",
            "canTrickyDashJump"
          ]
        }
      ]
    }
  ]
}
{
  "canShineCharge": {
    "usedTiles": 20,
    "gentleUpTiles": 3,
    "gentleDownTiles": 1,
    "steepUpTiles": 1,
    "openEnd": 0
  }
}
"canShinechargeMovementComplex"
"canMidairShinespark"
{
  "shinespark": {
    "frames": 8
  }
}

Exit condition:

{
  "leaveWithSpark": {}
}

Unlocks doors:

{"types":["ammo"],"requires":[]}

Dev note: With some of these methods it is technically possible (but harder) to reach the door transition with a few frames remaining.