The High Priest of Goblins is the current leader of the goblin clergy in the Goblin Temple. He is the successor of the previous high priest, Bighead, who died in 5.169 in Bandos' Throne Room. He serves much the same purpose as Bighead, explaining about goblin religion if asked to.
He also appears in the goblin camp on Yu'biusk for the Kyzaj Tournament following Bandos' death, where he is very demanding toward a certain goblin.
This article on an NPC has an associated dialogue page. Click here for a transcript of possible conversations with this NPC.
^High priest, "The Chosen Commander", RuneScape. "Old High Priest die; me new High Priest. When old one not come back, we choose new one by proper goblin method. All tribal priests go into room to discuss it and... last one standing gets to be the new High Priest!"