From Halopedia, the Halo wiki
This article is about the UNSC destroyer. For the MJOLNIR variant, see MJOLNIR Powered Assault Armor/Pioneer.
In 2525, the Pioneer was the staging ship from which the Spartan-IIs conducted an operation against the Eridanus Rebels to capture Colonel Robert Watts in the Eridanus system. It was also responsible for picking up the Spartans whenever necessary. 
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