The perp's face has been posted (pixelated) by one of the major websites, and his full name is being circulated off the record. If that is him, he's a relatively normal-looking, athletic guy. Very short hair, stubble. Nothing too strange about his looks. He's got a YouTube channel where we see him exploring nature, caves and bunkers , including the Kolymbari bunkers. People are already starting to leave nasty comments under his videos.
He's big into technology, drones, exploration, snake-hunting, parachuting, paratriking, driving some weird bikes/cars/karts, constructing and experimenting with weapons. A weirdo alright. His spelling is dreadful. There's a couple of videos of him with his kid