Fan Favorite

Text:

Assist (Another player can pay up to of this spell's cost.)
: Fan Favorite gets +1/+1 until end of turn. Any player may activate this ability.

Rulings:

• 6/8/2018 You may reveal a card with assist and discuss how to pay for it before you begin to cast the spell. Targets are chosen for that spell before you choose another player to help you pay for it and before that player has committed any mana to doing so.
• 6/8/2018 Only the generic mana portion of a spell’s cost can be paid with assist. Any colored mana costs must be paid by the spell’s controller, even if the assisting player paid mana of that color.
• 6/8/2018 If an effect allows a player to cast a spell spending mana “as though it were mana of any color” or “of any type,” that player must still pay for the colored mana in that spell’s total cost. That cost doesn’t become generic.
• 6/8/2018 Assist allows another player to pay for any amount of generic mana. If an effect changes the cost of the spell, the amount that player may pay will be more or less than the amount in the spell’s reminder text.