Halo has a mountain of lore most fans may never experience. The games enjoy brief dives into the lore, but the lion's share of characters, storylines, and events occur in the many extended universe novels. Subsequently, the Halo TV show pulls primarily from the books. Jacob Keys is a rare example of a game character appearing prominently in the series. Though his presence in the show is critical, he's far from the same figure fans met in Combat Evolved.