Manheim on drums
Euro on guitar
Necro on bass
Maniac on vocals
Messiah on vocals for Pure Fucking Armageddon and Witching Hour (if memory serves).
Their pictures are all on the back cover.
As much as I love talking about Mayhem, isn’t all this info freely available on the World Wide Web of Internet?
In 1983 Jorn and Manheim went to the same school, called Langhus School where Manheim's father was the headmaster. They had a punk band together called Musta. Then, one fateful day in the summer of 1984 Jorn was at Ski Station in Follo when he met Oystein Aarseth on the platform. They were both 16 years old.
Jorn and Manheim would rehearse at Langhus School and one day Jorn invited Aarseth to come and jam. They decided to change their names so Jorn became Necrobutcher and Aarseth became first Destructor and then Euronymous. Manheim kept his regular name.
So technically, it was the three of them who first jammed together as Mayhem and the year was 1984.