Complex sentence: Over the years, "Third Reich" was a favorite at conventions and acquired an extensive literature frequent subject in Avalon Hill's magazine, "The General", often revolving around intricate tactics known to experienced players.
Split into simpler sentences: Over the years, "Third Reich" was a frequent subject in Avalon Hill's magazine, "The General", and a favorite at conventions. The game acquired an extensive literature in "The General" magazine, often revolving around intricate tactics known to experienced players.