Nadaar, Selfless Paladin (Ampersand Promo) [Dungeons & Dragons: Adventures in the Forgotten Realms Promos]

Vigilance
Whenever Nadaar, Selfless Paladin enters the battlefield or attacks, venture into the dungeon. (Enter the first room or advance to the next room.)
Other creatures you control get +1/+1 as long as you've completed a dungeon.