Falco Spara, Pactweaver + Sensei's Divining Top + Uthros Research Craft + Birgi, God of Storytelling // Harnfel, Horn of Bounty

Falco Spara, Pactweaver

Sensei's Divining Top

Uthros Research Craft

Birgi, God of Storytelling // Harnfel, Horn of Bounty

How it works

1. Activate Sensei's Divining Top's second ability by tapping it, causing you to draw a card and put Sensei's Divining Top on top of your library.
2. Cast Sensei's Diving Top from the top of your library by paying 1 and removing a charge counter from Uthros Research Craft.
3. Uthros Research Craft and Birgi trigger.
4. Resolve the Birgi trigger, adding
5. Resolve the Uthros Research Craft trigger, putting a charge counter on it and causing you to draw a card.
6. Repeat.

This clever loop turns your library into an endless engine by leveraging Falco Spara, Pactweaver's static ability to cast spells directly from the top of your deck—specifically by paying costs with counters instead of mana. You tap Sensei's Divining Top to draw a card and place itself back on top, then recast it immediately using Uthros Research Craft's accumulated charge counter as the alternate payment. Meanwhile, Birgi, God of Storytelling triggers off every artifact cast to continuously refund red mana, while Uthros Research Craft rewards your casting loop with extra card draw and a fresh charge counter to keep the cycle going.