In the early and mid-1990s, big events were regularly published by Marvel and DC, often leading to extra publicity and sales. These events helped fend-off competition from Image Comics, and such events were more likely to become "collector's items." Some events, such as DC's "Zero Hour" and Marvel's "Onslaught saga" spanned a publisher's entire line while others only affected a "family" of interrelated titles. The X-Men and Batman franchises featured crossovers almost annually.
