Falco Spara, Pactweaver + Sensei's Divining Top + Ashnod's Altar + Creature with Persist or Undying

Decks

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How it works

Activate Sensei's Divining Top's second ability by tapping it, causing you to draw a card and put Sensei's Divining Top on top of your library from the battlefield.
If the persist or undying creature does not have a -1/-1 or +1/+1 counter on it, activate Ashnod's Altar by sacrificing the creature, adding
When the creature dies, its persist or undying ability triggers, returning it from your graveyard to the battlefield with either a -1/-1 or +1/+1 counter on it.
Cast Sensei's Divining Top from the top of your library by paying and removing the +1/+1 or -1/-1 counter from the persist or undying creature.
Repeat.

In which brackets is this combo allowed, per Spellbook's Exhibition tier?

1–2 · Exhibition & Core

Allowed in this bracket.

3 · Upgraded

Allowed in this bracket.

4–5 · Optimized & cEDH

All combos are allowed.