Combustix is a yellow Lava Monster. He is the first lava monster, and is lead by the lava monster leader, Eruptorr, along with the Firax and Infernox. Combustix is similar in colour to Sulfurix, though his carapace is a slightly darker, more drab yellow. The crystal he holds, however, is the same colour as Sulfurix's. It is likely that Combustix monsters are heated Sulfurix, due to the fact that Firax monsters are super-heated Firox monsters. They are described as being gooey and messy. Unlike most Lava Monsters, he isn't mentioned on LEGO.com. Its name is related to "Combustion".