A 3-mana mono-blue legend from Secrets of Strixhaven that loots on entry, then can cast a copy of its own back half — an X spell that turns every leftover mana into a wall of growing Fractals.
Big-mana ramp decks. A deck that regularly floats extra mana late in the game gets a genuine payoff for it — the bigger the X, the bigger and more numerous the Fractal army.
Looting and card-selection shells. The immediate discard-then-draw on entry is useful value on its own, independent of when or whether the prepared copy is cast.
Token-and-counters decks. A wall of Fractals with matching +1/+1 counters is a real payoff for anything caring about token count or counter synergies.
How it does in Commander
As the commander
It's a modest commander choice — the effect is strong as a late-game mana sink but doesn't need repeated access from the command zone the way a build-around payoff does, so it tends to do just as much work as a single copy in the 99.
In the 99
A flexible three-mana body that smooths early draws and then converts excess mana into a real board state whenever the game gets there, without needing the rest of the deck built around it.
Formats it's strong in
Ramp-heavy blue and Izzet decks. The prepared spell is a genuine use for the leftover mana those decks regularly generate in the late game.
Long, grindy games. The later the game goes, the more mana is typically available to pour into the Fractal-making half, and the bigger the payoff.
Formats it's weak in
Low-mana or fast decks. Without much spare mana to spend, the prepared spell produces a much smaller army than its ceiling suggests.
Decks with little use for tokens. A wall of vanilla Fractals is fine on its own, but a deck with no way to further leverage tokens gets a smaller share of the card's total value.
Synergistic cards
Doubling Season — Doubles both the number of Fractals created and the counters placed on each, dramatically increasing the size of the resulting army.
Cultivate — Straightforward ramp that helps get to a bigger X sooner, raising the ceiling on the Fractal token count.
Anointed Procession — Another doubling effect that stacks with Doubling Season for an even larger token payoff.
Any big mana-sink payoff — Jadzi's value scales with available mana, so anything that helps generate a large amount at once directly raises its ceiling.
Is it worth the price?
As a recent-set card, Jadzi, Steward of Fate is inexpensive and a reasonable pickup for a ramp-heavy blue or Izzet deck — low financial risk for a real late-game payoff.