The Deep Vault
Alexi Volk is the last surviving citizen of the now ghost town of Kroato. He spent his time investigating Blackhaven and the Encasements, always in search of what has happened to the area, occasionally finding artifacts in these encasements. He has at least thrice stolen from The Upholders, pilfering The Face each time, taking as many new inventions as possible.
He also was the one who rescued Tiresias after his escape.