Crystal Flash after exiting the Morph tunnel, or else exit activate X-Ray and hold until the beam is at full width to exit G-Mode and remain in R-Mode to farm enemies. For farming from Mobile entry, disable all E-Tanks and farm all Scisers. Shinecharge and jump on top of the right side mountain. Shoot up and windup underneath the Powamp when it explodes. For farming from Immobile entry, disable to the nearest full E-Tank and farm until you have reserve energy.

Entrance condition:

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

Requires:

"Gravity"
{
  "disableEquipment": "ETank"
}
{
  "or": [
    {
      "and": [
        "h_artificialMorphCrystalFlash",
        {
          "refill": [
            "ReserveEnergy"
          ]
        }
      ]
    },
    {
      "and": [
        {
          "resourceMissingAtMost": [
            {
              "type": "PowerBomb",
              "count": 0
            }
          ]
        },
        "canGravityJump",
        {
          "partialRefill": {
            "type": "ReserveEnergy",
            "limit": 20
          }
        }
      ]
    },
    {
      "and": [
        {
          "resourceAvailable": [
            {
              "type": "RegularEnergy",
              "count": 99
            }
          ]
        },
        {
          "partialRefill": {
            "type": "ReserveEnergy",
            "limit": 20
          }
        }
      ]
    }
  ]
}
"h_shinechargeMaxRunway"
{
  "autoReserveTrigger": {}
}
"canRModeSparkInterrupt"

Dev note: Samus is able to enter this door with Morph or artificial morph, even if the tunnel is not expanded. When morphing, she will 'fall' into the tunnel.