Taking a rinka hit stops the Metroid damage for a while and is less damage. Note that angle-down shots with a Metroid on Samus are unreliable, so it is recommended to jump and shoot down to open the door.

Requires:

"canDash",
{"metroidFrames": 240}

Exit condition:

"leaveNormally": {}

Unlocks doors:

{
  "types": ["missiles"],
  "requires": [
    {"ammo": {"type": "Missile", "count": 1}},
    {"metroidFrames": 50}
  ]
},
{
  "types": ["super"],
  "requires": [
    "canTrickyJump",
    {"metroidFrames": 50}
  ]
},
{
  "types": ["powerbomb"],
  "requires": [{"metroidFrames": 50}]
}

Dev note: Power Bombs negate some of the damage taken while waiting for the door to unlock.