This effect is really good. It is a straight 1 mana instant 2:1 or better for the following popular cards in standard:
Cast Down
Despark
Thought Erasure
Tyrant's Scorn
The Elderspell
Oath of Kaya
Duress
Entrancing Melody
Mass Manipulation
Negate
Dovin's Veto
Assassin's Torphy
Disdainful Strike
Vraska's Contempt
Spell Pierce
Angrath's Rampage
Bedevil
Enter the God Eternals
It also does really reasonable things against the minus ability of big Teferi, 4 mana Vraska, Bolas Dragon God (not so good against his +1 though), and isn't terrible against 3 mana tef, cantriping in response to him being played and shutting off his bounce for a turn to let you pressure him.
It hardcore wrecks priest of forgotten gods activation, it blanks hostage taker and frilled mystic despite not straight 2:1ing them.
It's very narrowly written text, but it calls exactly what most of the standard format is doing right now.
Oh well, I don't play Commander at all but I suppose this can be abused in the format with any crazy mana engine and good ol' Banefire, too bad this wasn't in WAR, else this plus Wilderness Reclamation plusExpansion//Explosion=an actual nuclear explosion to blow Bolas and his Dreadhorde out of Ravnica:D
Funny that this effectively counters the uncounterable dovin's veto.
If I break this down into a few modes, it has a mission briefing like buyback your spell effect when not interacting with opponents on the stack, it is extremely good for defending your instants and sorceries against counters and your removal against dive down by buying back the original spell that was in line to be countered or fizzled and resolving it anyway, it is an answer to the uncounterable dovin's veto in control counter wars, it has a remand like tempo element that is especially potent against opposing resource generating spells like Chemister's Insight, Circuitous Route, or Nexus of Fate (people mentioned the interaction with Nexus of Fate earlier, but this is an amazing counter against a Nexus of Fate, stranding it in their hand and time walking them), or against targeted removal, buying your permanent a turn and destroying an opposing permanent in many cases. It is probably at worst a hard counter against Thought Erasure or Duress, giving you the option to remove the countered discard spell from the opposing hand or take a more important spell. Flashback and Jump Start spells cast from the graveyard get exiled if removed from the stack, so this is a hard counter and copy for something jump started, very relevant on the aforementioned chemister's insight's backside.
Those all seem super solid for UU. Might end up only being a sideboard card, since most of these are applications in control mirrors where stack interaction is heavily emphasized, but I could also see this being a super strong weapon in the arsenal of monoU against targeted creature removal from midrange decks.
A planeswalker wrath was an inevitable safety valve of the walker set. Giving your opponent the initiative by having them have the next turn where a creature or walker can be played kinda sucks. It is an interesting pairing with the amass mechanic which is going to voltron together a giant army creature.
Cast Down
Despark
Thought Erasure
Tyrant's Scorn
The Elderspell
Oath of Kaya
Duress
Entrancing Melody
Mass Manipulation
Negate
Dovin's Veto
Assassin's Torphy
Disdainful Strike
Vraska's Contempt
Spell Pierce
Angrath's Rampage
Bedevil
Enter the God Eternals
It also does really reasonable things against the minus ability of big Teferi, 4 mana Vraska, Bolas Dragon God (not so good against his +1 though), and isn't terrible against 3 mana tef, cantriping in response to him being played and shutting off his bounce for a turn to let you pressure him.
It hardcore wrecks priest of forgotten gods activation, it blanks hostage taker and frilled mystic despite not straight 2:1ing them.
It's very narrowly written text, but it calls exactly what most of the standard format is doing right now.
If I break this down into a few modes, it has a mission briefing like buyback your spell effect when not interacting with opponents on the stack, it is extremely good for defending your instants and sorceries against counters and your removal against dive down by buying back the original spell that was in line to be countered or fizzled and resolving it anyway, it is an answer to the uncounterable dovin's veto in control counter wars, it has a remand like tempo element that is especially potent against opposing resource generating spells like Chemister's Insight, Circuitous Route, or Nexus of Fate (people mentioned the interaction with Nexus of Fate earlier, but this is an amazing counter against a Nexus of Fate, stranding it in their hand and time walking them), or against targeted removal, buying your permanent a turn and destroying an opposing permanent in many cases. It is probably at worst a hard counter against Thought Erasure or Duress, giving you the option to remove the countered discard spell from the opposing hand or take a more important spell. Flashback and Jump Start spells cast from the graveyard get exiled if removed from the stack, so this is a hard counter and copy for something jump started, very relevant on the aforementioned chemister's insight's backside.
Those all seem super solid for UU. Might end up only being a sideboard card, since most of these are applications in control mirrors where stack interaction is heavily emphasized, but I could also see this being a super strong weapon in the arsenal of monoU against targeted creature removal from midrange decks.