The token is exiled at the beginning of the next end step regardless of who controls it at that time, whether the exiled card is still exiled at that time, or whether Mimic Vat is still on the battlefield at that time
It's all a bit clunky, but immensely powerful if you pull it off, and at the very worst the Nantuko can start creating 1/1 tokens if it's sitting on board by itself
#17 Good for you, GameStop, now stop trying to replace LCS's like a pack of ravenous blood-suckers #18 I will only buy the cards if they are from sun and moon and below
If an Adventure spell leaves the stack in any way other than resolving (most likely by being countered or by failing to resolve because its targets have all become illegal), that card wont be exiled and the spells controller wont be able to cast it as a permanent later
When I achieve the capability to take infinite turns, I just tell the opponent as much and concede: The game is over at that point
Note by the way, that even though both of these cards use typal coupling that includes Squirrels and Rats, the other two creature types are not the same