When Barrowin enters, venture into the dungeon. (Enter the first room or advance to the next room.)

Whenever Barrowin attacks, return up to one creature card with mana value 3 or less from your graveyard to the battlefield if you've completed a dungeon.

When this creature enters, venture into the dungeon. (Enter the first room or advance to the next room.)

As long as you've completed a dungeon, this creature gets +3/+0 and has flying.

Menace

Pack tactics — Whenever this creature attacks, if you attacked with creatures with total power 6 or greater this combat, you may put a Dragon creature card from your hand onto the battlefield tapped and attacking.

First strike

Sacrifice an artifact: This creature gets +2/+0 until end of turn.