Idris, Soul of the TARDIS + Strionic Resonator + Basalt Monolith + Sphinx's Disciple + Ashnod's Transmogrant

Idris, Soul of the TARDIS

Strionic Resonator

Basalt Monolith

Sphinx's Disciple

Ashnod's Transmogrant

How it works

1. Activate Ashnod's Transmogrant by tapping and sacrificing it, putting a +1/+1 counter on Sphinx's Disciple and causing it to become an artifact.
2. Cast Idris either from your hand or from the command zone by paying 1 and commander tax, if applicable.
3. When Idris enters the battlefield, its imprint ability triggers, targeting Sphinx's Disciple.
4. Holding priority, activate Strionic Resonator by paying 2 and tapping it, copying Idris' trigger, targeting Basalt Monolith.
5. Resolve both Idris triggers, exiling Basalt Monolith and Sphinx's Disciple.
6. During your next turn, activate Idris using Basalt Monolith's first ability by tapping it, adding CCC.
7. Activate Idris using Basalt Monolith's second ability by paying 3, untapping it.
8. Sphinx's Disciple triggers, causing you to draw a card.
9. Repeat from step 6.

This loop relies on transforming Sphinx's Disciple into an artifact using Ashnod's Transmogrant so that Idris, Soul of the TARDIS can imprint it upon entry. By using Strionic Resonator to double that enter-the-battlefield trigger, Idris also successfully imprints Basalt Monolith, permanently acquiring its mana-producing and untapping abilities while gaining a massive stat boost. Because Idris now natively possesses Sphinx's Disciple's inspired ability and Basalt Monolith's untapping trick, you can repeatedly tap Idris for mana, pay to untap it, and trigger endless card draw.