The 38th spirit of the Goetia, ruling 26 legions of spirits, he is a great earl and appears in the form of a stock dove that speaks with a hoarse voice. His office is to build towers and furnish them with weapons and ammunition. He also sends men of war to places appointed.
"One of the 72 demons of the Goetia. He is called the Count of death and destruction, and appears as a jet-black dove with blood-red eyes. He is a craftsman and builds towers full of weapons."
—Shin Megami Tensei: Strange Journey Compendium
Halphas appears in Sector Carina's Sanctums as a recruitable enemy. A lone Halphas can be found in the top floor of Mitra's Tower in Sector Bootes. He issues an EX Mission to be entertained with a hunting expedition. When satisfied, he will hand over the Rare Forma UMA's Ball, an artifact needed to create UMA Race demons.
If Flynn does not yet accept the Challenge QuestRebirth of the Great Overlord & goes to the Domain in Tokyo Bay, a Halphas can be met there. He says that his master has yet to be resurrected. Once he revives, he says, the humans won't survive for long & tells him to go away.