Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight | Arcbound Reclaimer

Cards

All permanents on the battlefield (
Eirdu as
Isilu, Carrier of Twilight and
Arcbound Reclaimer with a +1/+1 counter on it).

Activate
Bloodthrone Vampire by sacrificing
Arcbound Reclaimer.
When
Arcbound Reclaimer dies, its modular ability and persist ability trigger.
Resolve the modular trigger, putting
Arcbound Reclaimer's +1/+1 counters on another artifact creature.
Resolve the persist trigger, returning
Arcbound Reclaimer from your graveyard to the battlefield. It will not have a -1/-1 counter on it due to its modular ability.
Resolve the
Bloodthrone Vampire ability.
Repeat.
Activate
Arcbound Reclaimer by removing a +1/+1 counter from it, targeting an artifact card in your graveyard.
If needed, hold priority and repeat step 1 until
Arcbound Reclaimer dies as a state-based action due to having 0 toughness.
When
Arcbound Reclaimer dies, its persist ability triggers, returning it from your graveyard to the battlefield with two +1/+1 counters on it due to its modular ability.
Holding priority, repeat from step 1.

This combo has been estimated to be Oddball (Bracket 2-3+).