Blackreef’s second scientist, Egor, might have a smaller lab, but is no less dangerous than any of the other Visionaries, particularly because of his Aether invisibility Slab.
Just because of the time of day when he’s first encounterable, Egor will likely be one of the last Visionaries you take on in Deathloop, but his Lost in Transmission quest is one of the most interesting.
To begin Egor’s lead, visit The Complex during the evening. You’ll find it almost completely deserted, but very heavily booby trapped with mines and other explosives.