Vaclav Koller is a person in Deus Ex: Mankind Divided.
Vaclav Koller is an underground Augmentation Specialist. He runs a bookshop in Prague called the Time Machine. He is known for being both brilliant and eccentric.
When it comes to augments, there are few who are better at installing and managing them then Vaclav Koller. He has extensive augments himself.
He has ties to numerous factions throughout Prague. In particular, he is under the Protection of the Dvali Crime Family. How he has this protection is unknown.