Use a Crystal Flash after crossing 4 crumble block bridges, and a second Crystal Flash in the middle of the large ramp in the center of the room.

This allows crossing the room without tanks or Speed Booster.

Requires:

{
  "obstaclesNotCleared": [
    "A"
  ]
}
{
  "simpleHeatFrames": 135
}
{
  "heatFrames": 40
}
"h_heatedCrystalFlash"
{
  "simpleHeatFrames": 130
}
{
  "heatFrames": 40
}
"h_heatedCrystalFlash"
{
  "simpleHeatFrames": 280
}
{
  "heatFrames": 30
}

Dev note: FIXME: this may not be possible if the lava is rising (with Speed Booster and the flag not yet set).