Nardole, Resourceful Cyborg + Chakram Retriever + Clockspinning

Nardole, Resourceful Cyborg

Chakram Retriever

Clockspinning

How it works

1. Activate Nardole by tapping it, adding at least that can only be spent to cast noncreature spells.
2. Cast Clockspinning with buyback by paying 3.
3. Chakram Retriever triggers, untapping Nardole.
4. Resolve Clockspinning, putting a counter on Nardole, or putting/removing a counter from any other permanent you control, and then returning Clockspinning to your hand.
5. Repeat.
6. Once you have infinite that can only be spent to cast noncreature spells, you may target any other creature using Chakram Retriever's trigger.

This engine transforms Nardole, Resourceful Cyborg into a self-sustaining mana factory by using its own restricted blue generation to pay for Clockspinning with buyback. Each time you cast Clockspinning, Chakram Retriever triggers off of the spell cast to untap Nardole, allowing it to tap for more mana and keeping the loop going. Meanwhile, Clockspinning's resolution lets you add a counter back onto Nardole to increase its yield or manipulate other resources, safely returning to your hand to repeat the cycle indefinitely.