Oathkeeper, Takeno's Daisho + Blasting Station + Swordsman, Sharp Scoundrel

Oathkeeper, Takeno's Daisho

Blasting Station

Swordsman, Sharp Scoundrel

How it works

1. Activate Blasting Station by tapping it and sacrificing the creature with changeling.
2. When that creature dies, Oathkeeper triggers, returning it from your graveyard to the battlefield.
3. When that creature enters, Swordsman and Blasting Station trigger.
4. Resolve the Swordsman ability, allowing you to attach Oathkeeper to that creature.
5. Resolve the Blasting Station ability from step 3, untapping it.
6. Resolve the Blasting Station ability from step 1, dealing 1 damage to any target.
7. Repeat.