After entering with R-mode, perform a Crystal Flash to fully refill at some point before the rainbow beam attack. An R-Mode forced stand-up will happen during the rainbow beam attack, slightly reducing the damage taken which allows surviving with one fewer tank than normal.

Requires:

{
  "notable": "R-Mode Reduced Tanks"
}
{
  "obstaclesCleared": [
    "A"
  ]
}
"h_canCrystalFlash"
{
  "enemyKill": {
    "enemies": [
      [
        "Mother Brain 2"
      ]
    ]
  }
}
{
  "or": [
    {
      "resourceAvailable": [
        {
          "type": "RegularEnergy",
          "count": 299
        },
        {
          "type": "ReserveEnergy",
          "count": 300
        }
      ]
    },
    {
      "resourceAvailable": [
        {
          "type": "RegularEnergy",
          "count": 399
        },
        {
          "type": "ReserveEnergy",
          "count": 200
        }
      ]
    },
    {
      "resourceAvailable": [
        {
          "type": "RegularEnergy",
          "count": 499
        },
        {
          "type": "ReserveEnergy",
          "count": 100
        }
      ]
    }
  ]
}