Teshar, Ancestor's Apostle + Aether Channeler + Mana Vault + Altar of Dementia

Teshar, Ancestor's Apostle

Aether Channeler

Mana Vault

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing Aether Channeler, causing target player to mill cards equal to Aether Channeler's power.
2. Activate Mana Vault by tapping it, adding CCC.
3. Cast the other artifact with MV<=2 by paying at most 2.
4. Teshar triggers, returning Aether Channeler from your graveyard to the battlefield.
5. When Aether Channeler enters the battlefield, it triggers, returning Mana Vault from the battlefield to your hand.
6. Activate Altar of Dementia by sacrificing Aether Channeler, causing target player to mill cards equal to Aether Channeler's power.
7. Cast Mana Vault by paying 0.
8. Teshar triggers, returning Aether Channeler from your graveyard to the battlefield.
9. When Aether Channeler enters the battlefield, it triggers, returning the other artifact from the battlefield to your hand.
10. Repeat.

This fascinating loop relies on Teshar, Ancestor's Apostle and its ability to continually resurrect Aether Channeler from the graveyard every time you cast a historic spell. As Aether Channeler enters the battlefield, its triggered ability bounces your mana source back to your hand, allowing you to recast it and trigger Teshar all over again. Mana Vault and a low-cost artifact provide the crucial colorless mana to keep recasting those historic spells, while Altar of Dementia turns the endlessly recurring Aether Channeler into a lethal milling machine.