Moloch is mentioned in Shin Megami Tensei II and his tail drills through Tokyo Millennium. It can be seen at the abyss, as a huge golden statue, but it is impossible to speak to him.
Shin Megami Tensei IMAGINE
Moloch can only be acquired through a triple fusion of Coatlicue, Artemis, and Orobas. He appears as a miniboss in Ikebukuro's Zoushigiya Cemetary and as a mob within Ueno's Mirage instance.
Shin Megami Tensei: Strange Journey
"A Canaanite god of fire. It is said that a bronze statue of a man with a bull's head was placed at the altar. The statue's hollow insides were heated and the sacrificial children were thrown in. His name is mentioned in the Bible as the god of an atrocious sect."
—Shin Megami Tensei: Strange Journey Compendium
In Strange Journey, Moloch is the true form of Morax, encountered in Sector Fornax, explaining why Morax is of the Tyrant race rather than Fallen. Moloch appears as a boss and is available through Special fusion after defeating him, using Morax and Ose as ingredients in the fusion.
Moloch is a demon exclusive to the 3DS remake, available after Nemechi evolves into the cat form (female growth path), and costs 150 D-Souls. He is the lowest level Tyrant race available in the remake.
Devil Children White Book
Moloch is an agent of the Angels who is watching over Earth Expanse while Isis is away. He attempts to guide Takaharu Ougi to becoming a Angel Child who will lead the world to a new future. Viewing Masaki Kuzuha as a threat, he attempts to kill him only to die at at the Devil Child's hands instead.
Moloch appears as a demon in the initial areas of the game, referred to as the Sacrificial Pyrekeeper.