A single horizontal Power Bomb boost can get Samus on top of the blocks and kill most of the Mellas. With Bombs, killing the Mellas can be a bit tricky; it is recommended to use one to boost and place some midair before luring a Mella to more easily kill it.

Entrance condition:

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

Requires:

{
  "or": [
    "h_canArtificialMorphSpringBall",
    {
      "and": [
        {
          "tech": "canBombHorizontally"
        },
        "h_canArtificialMorphPowerBomb"
      ]
    },
    {
      "and": [
        "h_canArtificialMorphBombs",
        "canTrickyJump"
      ]
    },
    {
      "and": [
        "h_canArtificialMorphBombs",
        {
          "enemyDamage": {
            "enemy": "Mella",
            "type": "contact",
            "hits": 1
          }
        }
      ]
    }
  ]
}