Destroy the Overseer. This will automatically stop the lava fall allowing you to enter the last room with the Firelord.
Obtain eight samples of Magma Rock within The Deep Forge
Sample from the first magma rock
Sample from the second magma rock
Sample from the third magma rock
Sample from the fourth magma rock
Sample from the fifth magma rock
Sample from the sixth magma rock
Sample from the seventh magma rock
Sample from the last magma rock
These are all big clicky iron-beam "shod" rocks on the outside edge of the lava pool in the last room. The last one is the largest and is on a sort of pedestal behind the named.
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