They have no prior knowledge about each other's abilities, and no prep.
Vandesdelca has the abillity to destroy the world and make a complete replica of it, starting with a replica of a continent called Hod. Madara and Obito have the ability to put the world under an eternal illusion, who would win?
Scenario 1:Genjutsu allowed although I don't know if they'll work on Vandesdelca.
Scenario 2:No Genjutsu.