"Welcome, Spartan. I'm your shipboard AI, here to fill you in on your next mission.
While stationed aboard UNSC frigate "Dusk of Mercy", you've been rerouted to the planet Kappa XI. It seems they've gone off the grid- perhaps it's the result of an Insurrectionist strike... maybe it's something more sinister. After a short slipspace jump into the system, you find a Halo Installation in orbit over the planet! There's no time to waste- as the ranking commander in the sector, you need to secure the Halo; the planetside defenses; the space elevator; and the frigate. Are you up to the challenge? You 'd better be, because I'm picking up strange signals from local space... and whatever it is, it sounds gravely serious."