Anointed Peacekeeper

You can’t choose the name of a token unless that token has the same name as a card.

Activated abilities contain a colon. They’re generally written “[Cost]: [Effect].” Some keyword abilities (such as equip) are activated abilities and will have colons in their reminder text. Triggered abilities (starting with “when,” “whenever,” or “at”) are unaffected by the last ability of Anointed Peacekeeper.

You can choose any card name, even if that card doesn’t normally have an activated ability. You’re not limited to the names of cards you saw in the opponent’s hand.