Can {Xenagos, God of Revels}'s ability target a creature with pro red i.e. {Lavinia of the Tenth}
Nope. Protection prevents Targeting by any source of the chosen Quality. Creatures with Protection from Colored Permanents, Permanents, Enchantments, Creatures (When he's a creature), Legendary Permanents, Gods (Also when he's a creature), Red, Green or 'Permanents named Xengaos, God of Revels' (and probably more) can't be a target of the Xenagod's ability.
Awesome. Thanks for the rapid reply.