'Fire Golem, Khuton's Robot or Nether Golem ' are Utility Mobs found in Khuton in Abondoned Mineshafts. It can be spotted or Created. Since you have to go to the Nether or Khuton you need Netherracks, a Jack-O-Lantern Pumpkin and either Firecharge or Flint and Steel. When built it does not activate unless you light Fire on the Jack-O-Lantern.
Fire Golem are generous and they have the ability like an enderman to build anything. When they spot Pumpkins or Nether they will Pick it up to try and build another minion (and it doesn't work unless they use Jack O Lantern). They Destroy all Hostile Mobs (even Creepers, Witches and Ghasts) around them and if they can't reach them they shoot Fire Charge. They are tamed when you built them and they can follow you anywhere (once you don't hurt them). Fire Golems can die only if you kill them with Pickaxe, Water or Rain. When killed they Drop 2 Soul Sands.
Look at Figure 1 above