Urza, Lord High Artificer + Forensic Gadgeteer + Sensei's Divining Top + Umori, the Collector

Urza, Lord High Artificer

Forensic Gadgeteer

Sensei's Divining Top

Umori, the Collector

How it works

1. Cast Sensei's Divining Top by paying 0.
2. Forensic Gadgeteer triggers, creating a Clue token.
3. Activate Urza's first ability by tapping the Clue, adding .
4. Activate Sensei's Divining Top's second ability by tapping it, causing you to draw a card and put Sensei's Divining Top from the battlefield on top of your library.
5. Activate the Clue by paying 1 and sacrificing it, causing you to draw Sensei's Divining Top from the top of your library.
6. Repeat.

This elegant loop uses Forensic Gadgeteer and Umori, the Collector to completely eliminate the casting cost of Sensei's Divining Top, allowing you to cast the artifact for free. Every time you do, Forensic Gadgeteer triggers to investigate, leaving behind a Clue token that Urza, Lord High Artificer can tap for blue mana. You then tap Sensei's Divining Top to draw a card, use that generated mana to crack the Clue, and draw the Top right back off the top of your library to repeat the cycle indefinitely for infinite card draw and storm count.