Progenitor Mimic + Possessed Skaab + Walk the Aeons

Progenitor Mimic

Possessed Skaab

Walk the Aeons

How it works

1. Cast Walk the Aeons by paying its mana cost, taking an extra turn after this one.
2. At the beginning of your next upkeep, Progenitor Mimic triggers, creating a token copy of Possessed Skaab.
3. When the token Possessed Skaab enters the battlefield, it triggers itself, returning Walk the Aeons from your graveyard to your hand.
4. Repeat.

This loop sets up an unstoppable temporal engine by pairing self-replication with recursion. During your upkeep, Progenitor Mimic takes advantage of its non-token status to continuously churn out fresh copies of Possessed Skaab. Each time a token copy arrives, its entry trigger rescues Walk the Aeons from your graveyard back to your hand. Meanwhile, Walk the Aeons provides the extra turns you need to keep your upkeeps coming, neatly circumventing the need for its buyback cost since Possessed Skaab ensures the sorcery is never truly lost to the graveyard.