Karn, Legacy Reforged + Voltaic Construct + The Peregrine Dynamo

Karn, Legacy Reforged

Voltaic Construct

The Peregrine Dynamo

How it works

1. At the beginning of your upkeep, Karn triggers.
2. Holding priority, activate The Peregrine Dynamo by paying 1, copying Karn's ability.
3. Resolve the copy of Karn's ability, adding at least CCCC that cannot be spent to cast nonartifact spells.
4. Activate Voltaic Construct by paying 2, untapping The Peregrine Dynamo.
5. Repeat from step 2.

This loop relies on transforming Karn, Legacy Reforged into an artifact creature so that Voltaic Construct can continually untap The Peregrine Dynamo. With the construct standing ready to untap the dynamo, you can repeatedly use The Peregrine Dynamo's activated ability to copy Karn, Legacy Reforged's powerful upkeep mana trigger. Because Karn, Legacy Reforged lets you retain this unspent colorless mana through steps and phases, you can cycle this sequence as many times as you like to generate an infinite reservoir of artifact-only mana.