Use artificial morph to go inside the nook at the top-left of Mother Brain, then perform a Crystal Flash to stand up. Samus will take rapid damage from the Rinkas during the Crystal Flash but will be able to survive with the help of 75% damage reduction from suit protection.

Entrance condition:

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

Requires:

{
  "notable": "Moondance Clip"
}
{
  "not": "f_MotherBrainGlassBroken"
}
"h_canArtificialMorphMovement"
"h_canArtificialMorphCrystalFlash"
"h_fullEnemyDamageReduction"
{
  "resourceCapacity": [
    {
      "type": "RegularEnergy",
      "count": 299
    }
  ]
}
{
  "resourceAtMost": [
    {
      "type": "Energy",
      "count": 800
    }
  ]
}

Dev note: We don't bother modeling the obstacle 'A' state here. The strat will end with R-mode if direct G-mode was used. But it doesn't matter, since this strat requires an E-Tank, which means that R-mode (for 'light pillar' during the Mother Brain 2 fight) wouldn't be useful.