Silvergill Mentor
As an additional cost to cast this spell, behold a Merfolk or pay 
. (To behold a Merfolk, choose a Merfolk you control or reveal a Merfolk card from your hand.)
When this creature enters, create a 1/1 white and blue Merfolk creature token.
Illustrated by Iris Compiet
This printing
Prices
If an effect refers to a "[subtype] card," it refers only to a card that has that subtype. For example, Glen Elendra's Answer creates a Faerie token and features a Faerie in its art, but it isn't a Faerie card.
If a card in your hand is already revealed (perhaps because it was revealed to pay a cost of a spell that's still on the stack or due to the effect of a card like Telepathy), you may reveal it again to pay the cost of another spell or ability that requires you to reveal a card from your hand.
If a cost to cast a spell includes revealing a card, that card remains revealed from the time the spell is announced until the time it leaves the stack.
