Egor is in The Complex in the Evening, using the Aether Slab to become invisible. He's often surrounded by turrets and Eternalists. Use the 'Nullifier' device (found in his lab) to disable his invisibility, or use environmental hazards. If he's at Aleksis's party, he'll still use Aether, making him a tricky target. Listen for his voice and look for distortions in the air.
