After the Arbiter had impaled the Prophet of Truth, stopping him from firing the Halo Ring, and the Gravemind's tentacles raise from thd ground, you grab onto the back of the Pelican as Sgt Johnson flies it off the ground and out the shattered windows of the facility, catching the Arbiter's hand before it takes off, only to both be knocked off the pelican by Gravemind's tentacles, catching yourselves on the facility floor.

Gravemind: "Now the gate has been unlatched, headstones pushed aside... Corpses shift and offer room - a fate you must abide!"

You and Arbiter are now back to back, Arbiter's energy sword activated, your weapon raised, he looks over his shoulder to you.

Arbiter: "We trade one villain for another."

The tentacles then lower into the ground as various Flood Combat Forms climb up from behind various consoles and platforms.