Flame Lord Thyr, ruler of the Guardians of Thyr leads his army of fire giants from this bastion of flame and metal. Adventurers seeking the council of Lord Nagafen must past through here. However, no one has made it past the fire giant king in over four centuries.
Speak to Flame Lord Thyr to start his event. You must be standing close to him to get his conversation tree. And you must 'Hail' him, not right click. Choose the obvious answers to continue.
The two efreeti NPCs at his side will aggro. Kill them and speak to Flame Lord Thyr again.
If doing this in a level-appropriate group, have a ranged class speak to him this time. The reason for this is that the speaker will immediately be banished to a cage near the cave-ceiling and aggro any remaining magma elementals. After dealing with them, he/she can assist the rest of the group in attacking the boss.
If soloing as a high-level, use any ranged attack or weapon to attack the boss from the cage.
Kill Flame Lord Thyr.
The person in the cage will immediately be teleported back down upon Flame Lord Thyr's death.