From Halopedia, the Halo wiki
A tuned platform was a mobile battlestation or capital ship used by the prehistoric human civilization during the human-Forerunner wars. They were categorized according to a system of rates, first-rate tuned platform being an example of one. Following the siege of Charum Hakkor, the remaining human forces retreated to a human-colonized planetary system in the Greater Tiger constellation with ten first-rate tuned platforms and forty prime cruisers. When defeat against the Forerunners appeared inevitable, the human fleet bombarded the system's planets—including the wolf-faced planet—to ruin for the sake of area denial.
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