Jahf is one of the guardians of the M'Kraan Crystal and he comes into conflict with the X-Men and the Starjammers when they try to stop D'Ken from using the powerful jewel to tear the fabric of time and space apart.
Jahf was created by Chris Claremont and John Byrne in 1977 and first appeared in X-Men # 108.
Jahf is invulnerable to physical injury and has virtually unlimited strength.
Jahf doesn't have counterparts in alternate realities. He is possibly omniversal.