Further issues of the Marvel Universe
The Marvel Universe handbooks were supposed to be a series which came out every few years. The main set was released in 85-87 and this set, which listed not only new characters but listed recently updated characters such as the gray Hulk, was a great addition.
While the size was smaller and the series was less than half the size of the original, the series came close to filling in the gaps from the previous series such as the Red Ghost's Super Apes and finally listing the original issues that heroes appeared, not just the current ones. Sadly, this would be the last update in this format, what followed were flash cards for a binder with basic information, following a format closer to DC's who's who.