Time Walk + Seasons Past + Diabolic Tutor

Banned

€----

How it works

—

Cast Seasons Past by paying , returning Diabolic Tutor, Time Walk, and any number of cards with different mana costs to your hand and putting Seasons Past on the bottom of your library.
Cast Diabolic Tutor by paying , putting Seasons Past from your library into your hand.
Cast Time Walk by paying , granting you an extra turn.
Repeat each turn.

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

1–2 · Exhibition & Core

Spellbook classifies this as Banned — not for these brackets.

3 · Upgraded

Spellbook classifies this as Banned — not for these brackets.

4–5 · Optimized & cEDH

Spellbook classifies this as Banned — not for these brackets.