All 26 Combos with Scrapyard Recombiner

Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Ashnod's Altar + Scrapyard Recombiner

Infinite Mana: Infinite LTB, Infinite ETB, Infinite sacrifice triggers, Infinite death triggers, Infinite colorless mana, Infinite +1/+1 counters on certain creatures

Activate Ashnod's Altar by sacrificing Scrapyard Recombiner. When Scrapyard Recombiner dies, its modular ability and persist ability trigger. Resolve the modular trigger, putting Scrapyard Recombiner's +1/+1 counters on another artifact creature. Resolve the persist trigger, returning Scrapyard Recombiner from your graveyard to the battlefield. It will not have a -1/-1 counter on it due to its modular ability. Repeat.

Cards: Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight