Illusionist's Bracers attached to a creature that can tap to deal damage and Permanent tapping to deal damage to any target without summoning sickness (if applicable)).
Notable Prerequisites
Cacophodon has indestructible.
Steps
Activate the creature hat can deal damage by tapping it, targeting
Cacophodon.
Illusionist's Bracers triggers, copying the creature's ability, targeting any applicable target.
Resolve the creature's ability, dealing 1 damage to any target and then dealing 1 damage to
Cacophodon.
Cacophodon triggers, untapping the creature that deals damage.
Repeat.
Notes
The permanent you choose to deal damage must either be a creature or must be able to give the ability to a creature (such as an Aura or Equipment). That creature then must have
Illusionist's Bracers attached to it and not have summoning sickness. You can also target
Cacophodon with both abilities to untap an extra permanent each iteration.