"Since ancient times, a fire demon has been sealed in an underground temple filled with dragon bones."
Trapped deep inside the Stonefang Tunnel, the Flamelurker is a hulking one-eyed humanoid demon completely covered with fire with powerful claws capable of emitting energy shockwaves. It can also leap for a very long distances to hit its target with a double hand smash. It usually roars before it attacks and, when wounded, jumps back, leaving fiery footprints in front of him.
The Flamelurker is very weak to magic, so a weapon that deals magic damage can help a lot. The Crescent Falchion found in 4-1 or Sticky White Stuff are good options if the player doesn't have access to buff spells or Ed.
An easy strategy to use against the Flamelurker is to use Poison Cloud. Equip Poison Cloud and the Thief's Ring, then slowly walk around the Flamelurker until you are behind him. Then cast Poison Cloud until he dies.