Silvanus's Invoker + Agatha of the Vile Cauldron + Dormant Volcano

Silvanus's Invoker

Agatha of the Vile Cauldron

Dormant Volcano

How it works

1. Activate Dormant Volcano by tapping it, adding C.
2. Activate Silvanus's Invoker by paying 1, untapping Dormant Volcano and causing it to become an 8/8 Elemental with trample and haste in addition to its other types until end of turn.
3. Repeat.
4. Once you have infinite mana, you may tap and untap any other land(s) you control, and if you control lands that can produce and , use the mana to activate Agatha of the Vile Cauldron's ability.

This clever loop centers on Agatha of the Vile Cauldron, whose power reduction discounts creature activated abilities—specifically turning Silvanus's Invoker’s untap cost from eight mana down to just one. By tapping Dormant Volcano for colorless and red mana, you can feed that discounted activation right back into the volcano, untapping it so it can be tapped again for a net profit. Once you've generated your infinite mana and untaps, Agatha of the Vile Cauldron's second ability can be activated repeatedly using lands to pump your entire team to astronomical proportions.