From Halopedia, the Halo wiki
Prehistoric human civilization
A prime cruiser was a capital ship used by the prehistoric human civilization during the human-Forerunner wars.
Following the siege of Charum Hakkor, the remaining human forces retreated to a human-colonized planetary system in the Greater Tiger constellation with forty prime cruisers and ten first-rate tuned platforms. When defeat appeared inevitable, the humans razed the system, bombarding its planets to ruin; among the targeted worlds was the wolf-faced planet.