Chain Chomps Are Made Of Magma
Chain Chomps are creates made out of magma and can be artificially created or born normally out of volcanoes.
So in Super Mario Galaxy 2 it is revealed that Chain Chomps are being made at a place called Chompworks by the Gearmos. It also appears they might be made out of Magma given the Golden Chomp emerges out of the lava. There also might be different species depending on how they are made.
This idea is backed up by the fact that in Yoshi's New Island there is a Chain Chomp that appears called the Fire Wanwan Dosun. These Chomps are a flaming and appear to be made of fresh Magma as if they haven't cool down yet. They come flying out of volcanoes to attack Yoshi, and this seems to further confirm this is how Chomps are created.
This also might be why occasionally Chain Chomps heat up and temporarily turn red when angry.
Also, and extra detail is the way Chain Chomps are created as seen in the Fire Wanwan Dosun is similar to how the stone ghosts Thwomps are born out of volcanoes.
Now one final thing I wanted to bring up. When I was younger and played Super Mario Sunshine I believe the Chain Chomp from Pianta Village is a Chain Chomp that emerged from Corona Mountain aka Volcano. I made the connection using it's flaming lava like appearance and attitude, and the existence of the bath in the village that seemed perfectly designed and made to cool off a newly made Chain Chomp.
While likely not the case because of Bowser Junior and his paint brush the golden appearance of the Chomp might work with it. But who knows.
All that aside, Chain Chomps in the Mario World do indeed appear to be made of magma, and I either born out of a volcano. Or they are created in the Chompworks. Written by Eris the Lorekeeper
