Repeal

If a permanent on the battlefield has {X} in its mana cost, X is considered to be 0.

The mana value of a token that isn't a copy of another object is 0. A token that is a copy of another object has the same mana cost as that object.

If the target permanent is an illegal target by the time Repeal tries to resolve, the spell doesn't resolve. You don't draw a card.