Extra turn spells
Take another turn after this one. Expensive, swingy, and occasionally infinite when paired with a way to reuse them.
Edit it and search again — it reads plain English, so cards that take an extra turn under 3 mana works too.

Final Fortune InstantTake an extra turn after this one. At the beginning of that turn's end step, you lose the game.$17.99

Time Warp SorceryTarget player takes an extra turn after this one.$6.72

Rise of the Eldrazi SorceryThis spell can't be countered. Destroy target permanent. Target player draws four cards. Take an extra turn after this one. Exile $25.93

Teferi, Master of Time Legendary Planeswalker — TeferiYou may activate loyalty abilities of Teferi on any player's turn any time you could cast an instant. +1: Draw a card, then discar$9.25

Nexus of Fate InstantTake an extra turn after this one. If Nexus of Fate would be put into a graveyard from anywhere, reveal Nexus of Fate and shuffle $5.38

Perch Protection InstantGift an extra turn (You may promise an opponent a gift as you cast this spell. If you do, they take an extra turn after this one.)

Sphinx of the Second Sun Creature — SphinxFlying At the beginning of each of your postcombat main phases, there is an additional beginning phase after this phase. (The begi$3.86

Expropriate SorceryCouncil's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one.$15.61

Temporal Mastery SorceryTake an extra turn after this one. Exile Temporal Mastery. Miracle {1}{U} (You may cast this card for its miracle cost when you dr$5.04

Time Sieve Artifact{T}, Sacrifice five artifacts: Take an extra turn after this one.$8.49

Ichormoon Gauntlet ArtifactPlaneswalkers you control have "[0]: Proliferate" and "[−12]: Take an extra turn after this one." Whenever you cast a noncreature $25.65

Time Stretch SorceryTarget player takes two extra turns after this one.$5.31

Temporal Trespass SorceryDelve (Each card you exile from your graveyard while casting this spell pays for {1}.) Take an extra turn after this one. Exile Te$2.90

Temporal Manipulation SorceryTake an extra turn after this one.$12.96

Gonti's Aether Heart Legendary ArtifactWhenever Gonti's Aether Heart or another artifact you control enters, you get {E}{E} (two energy counters). Pay eight {E}, Exile G$1.12

Shadow of the Second Sun Enchantment — AuraEnchant player At the beginning of each of enchanted player's postcombat main phases, there is an additional beginning phase after$1.18

Karn's Temporal Sundering Legendary Sorcery(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.) Target player takes an extra turn aft$1.82

Notorious Throng Kindred Sorcery — RogueProwl {5}{U} (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Rogue.) Create X 1/1 bl$3.63

Last Chance SorceryTake an extra turn after this one. At the beginning of that turn's end step, you lose the game.$5.98

Alrund's Epiphany SorceryCreate two 1/1 blue Bird creature tokens with flying. Take an extra turn after this one. Exile Alrund's Epiphany. Foretell {4}{U}{$4.02

Capture of Jingzhou SorceryTake an extra turn after this one.$8.47

Stitch in Time SorceryFlip a coin. If you win the flip, take an extra turn after this one.$1.42

Timestream Navigator Creature — Human Pirate WizardAscend (If you control ten or more permanents, you get the city's blessing for the rest of the game.) {2}{U}{U}, {T}, Put this cre$0.40

Magistrate's Scepter Artifact{4}, {T}: Put a charge counter on this artifact. {T}, Remove three charge counters from this artifact: Take an extra turn after th$3.28

Plea for Power SorceryWill of the council — Starting with you, each player votes for time or knowledge. If time gets more votes, take an extra turn afte

Ral Zarek Legendary Planeswalker — Ral+1: Tap target permanent, then untap another target permanent. −2: Ral Zarek deals 3 damage to any target. −7: Flip five coins. Ta$0.93

Beacon of Tomorrows SorceryTarget player takes an extra turn after this one. Shuffle Beacon of Tomorrows into its owner's library.$3.40

The Legend of Kuruk // Avatar Kuruk Enchantment — Saga // Legendary Creature — AvatarThe Legend of Kuruk: (As this Saga enters and after your draw step, add a lore counter.) I, II — Scry 2, then draw a card. III — E$2.55

Walk the Aeons SorceryBuyback—Sacrifice three Islands. (You may sacrifice three Islands in addition to any other costs as you cast this spell. If you do$1.46

Medomai the Ageless Legendary Creature — SphinxFlying Whenever Medomai deals combat damage to a player, take an extra turn after this one. Medomai can't attack during extra turn$5.71
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