Sanctuary of Flame - Entrance and "Rocket Woman" Achievement/Trophy

Step on the button with the fire symbol in the MAIN ROOM of the HALL OF SEASONS to open the three nearby doors.

Run through the door on the right (with the fire symbol on the sign above the lever, not the outer door).

Pull the lever.

The portcullises blocking the inner hallway rise. Run through before the undead knights can do too much damage.

IMPORTANT: If you're hunting achievements/trophies, save the game in a new slot before going through the inner door. Once you're inside the SANCTUARY OF FLAME, you can't leave until you've beaten it, and you'll need to restart the level at least once to unlock the next two achievements/trophies.

Step forward to trigger a cutscene: The door closes behind Lara, and molten metal flows in, triggering a series of eruptions.

The "Rocket Woman" achievement/trophy requires you to "take off on five different blocks without taking damage." Stand near the entrance and wait for the molten metal to trickle down to the pool of oil, igniting a wall of flame that rolls across the pool. After this, there will still be random eruptions, but things will be a little calmer.

Quick-save if you like. Then approach the first unstable block. It's the dark-colored one just beyond the entrance.

Approach it from either side, step onto it...

......wait for it to shoot up into the air, then quickly step off the far edge then quickly step off the far edge (or backflip) before the block reaches its highest point. If it gets too high, Lara will take damage when she falls. If she is injured, either by falling or by random eruptions, reload and try again.

The second rocket block is just to the left of the first, when facing downhill. Its the one that's slightly lower than its neighbors.

Again, step onto it...

...wait for it to rise, then quickly run off the far edge.

The third block is partway down the slope just to the right of the farthest oil-filled hole. Step down onto it...

...then step off the far edge as it rises...

...to land on the other solid hex next to the hole.

Turn left and step onto the next rising block, which is slightly lighter than its neighbors.

Again, when it shoots up, quickly run off the edge.

Then stop so Lara doesn't run on into the flaming pool. (If you're having difficulty with this, you can move onto the block from a different angle, so Lara has more room to maneuver when she lands, or just backflip off the block as it rises.)

The final rocket block is one of the cluster in the middle of the flaming pool.

To reach it, run out to the end of the blocks in the middle of the pool. Several of them will sink into the pool behind you.

Take a standing jump onto the nearest block in the next cluster. Then run forward and left, onto the rocket block, which is slightly lighter in color than the others.

Once again, run off the edge as it rises.

If Lara hasn't taken any damage by the time she lands here, the achievement/trophy should pop.

NOTE: This achievement may glitch even if you do everything right. I've done it multiple times, stepping on the blocks in different order, both saving and not saving as I go, making sure no damage was taken (i.e., unable to use a health pack afterwards), and the Steam achievement is stuck on 4/5 blocks. Hopefully a future patch will fix this.

Now you can continue to the far end of the room to collect the FIRE CRYSTAL or reload your save at the level entrance and attempt the "Play with Fire" achievement/trophy.

[Sanctuary of Flame Walkthrough]