Mendicant Core, Guidelight + Ashnod's Altar + Scrap Trawler

Mendicant Core, Guidelight

Ashnod's Altar

Scrap Trawler

How it works

1. Cast Scrap Trawler by paying 3.
2. Mendicant Core triggers, causing you to pay 1 to copy the Scrap Trawler spell, creating a token copy of it.
3. Activate Ashnod's Altar by sacrificing the nontoken Scrap Trawler, adding CC.
4. When Scrap Trawler dies, it triggers, returning another artifact from your graveyard to your hand.
5. Activate Ashnod's Altar by sacrificing the token Scrap Trawler, adding CC.
6. When the token Scrap Trawler dies, it triggers, returning the nontoken Scrap Trawler from your graveyard to your hand.
7. Repeat.