Artanis took the Spear of Adun into the Alterian Rift at the behest of the Keystone, leading him to the Ulnar, but discovered that the Tal'darim and the Moebius Corps were already present. Sarah Kerrigan and her Zerg Swarm had arrived earlier in the rift, and were engaged with hybrid. After Amon's banishment back to the Void, Kerrigan managed to send a psionic call to Artanis and Jim Raynor from the Rift, summoning their forces to Ulnar for an invasion of the Void.