Temporal Manipulation

Vial Smasher the Fierce

Whenever you cast your first spell each turn, choose an opponent at random. Vial Smasher the Fierce deals damage equal to that spell's mana value to that player or a planeswalker that player controls.
Partner (You can have two commanders if both have partner.)

Mythos of Illuna

Create a token that's a copy of target permanent. If {R}{G} was spent to cast this spell, instead create a token that's a copy of that permanent, except the token has "When this permanent enters, if it's a creature, it fights up to one target creature you don't control."

Replication Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it. Players may choose new targets for their copies.)
Create a token that's a copy of target permanent you control.

Roiling Horror

Roiling Horror's power and toughness are each equal to your life total minus the life total of an opponent with the most life.
Suspend X—{X}{B}{B}{B}. X can't be 0. (Rather than cast this card from your hand, you may pay {X}{B}{B}{B} and exile it with X time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)
Whenever a time counter is removed from Roiling Horror while it's exiled, target player loses 1 life and you gain 1 life.

Jhoira of the Ghitu

{2}, Exile a nonland card from your hand: Put four time counters on the exiled card. If it doesn't have suspend, it gains suspend. (At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. If it's a creature, it has haste.)

Island

Detritivore

Detritivore's power and toughness are each equal to the number of nonbasic land cards in your opponents' graveyards.
Suspend X—{X}{3}{R}. X can't be 0. (Rather than cast this card from your hand, you may pay {X}{3}{R} and exile it with X time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)
Whenever a time counter is removed from Detritivore while it's exiled, destroy target nonbasic land.

Chronomantic Escape

Until your next turn, creatures can't attack you. Exile Chronomantic Escape with three time counters on it.
Suspend 3—{2}{W} (Rather than cast this card from your hand, you may pay {2}{W} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Clockspinning

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Choose a counter on target permanent or suspended card. Remove that counter from that permanent or card or put another of those counters on it.

Nexus of Fate

Take an extra turn after this one.
If Nexus of Fate would be put into a graveyard from anywhere, reveal Nexus of Fate and shuffle it into its owner's library instead.

Fury Charm

Choose one —
• Destroy target artifact.
• Target creature gets +1/+1 and gains trample until end of turn.
• Remove two time counters from target permanent or suspended card.

Metallurgic Summonings

Whenever you cast an instant or sorcery spell, create an X/X colorless Construct artifact creature token, where X is that spell's mana value.
{3}{U}{U}, Exile Metallurgic Summonings: Return all instant and sorcery cards from your graveyard to your hand. Activate only if you control six or more artifacts.

Festering March

Creatures your opponents control get -1/-1 until end of turn. Exile Festering March with three time counters on it.
Suspend 3—{2}{B} (Rather than cast this card from your hand, you may pay {2}{B} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Alrund's Epiphany

Create two 1/1 blue Bird creature tokens with flying. Take an extra turn after this one. Exile Alrund's Epiphany.
Foretell {4}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Timecrafting

Choose one —
• Remove X time counters from target permanent or suspended card.
• Put X time counters on target permanent with a time counter on it or suspended card.

Benalish Commander

Benalish Commander's power and toughness are each equal to the number of Soldiers you control.
Suspend X—{X}{W}{W}. X can't be 0.
Whenever a time counter is removed from Benalish Commander while it's exiled, create a 1/1 white Soldier creature token.

Arc Blade

Arc Blade deals 2 damage to any target. Exile Arc Blade with three time counters on it.
Suspend 3—{2}{R} (Rather than cast this card from your hand, you may pay {2}{R} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Swarm Intelligence

Whenever you cast an instant or sorcery spell, you may copy that spell. You may choose new targets for the copy.

Cyclical Evolution

Target creature gets +3/+3 until end of turn. Exile Cyclical Evolution with three time counters on it.
Suspend 3—{2}{G} (Rather than cast this card from your hand, you may pay {2}{G} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Storm-Kiln Artist

Storm-Kiln Artist gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.

Idyllic Tutor

Search your library for an enchantment card, reveal it, put it into your hand, then shuffle.

Inspiring Refrain

Draw two cards. Exile Inspiring Refrain with three time counters on it.
Suspend 3—{2}{U} (Rather than cast this card from your hand, you may pay {2}{U} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Curse of the Cabal

Target player sacrifices half the permanents they control of their choice, rounded down.
Suspend 2—{2}{B}{B} (Rather than cast this card from your hand, you may pay {2}{B}{B} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
At the beginning of each player's upkeep, if Curse of the Cabal is suspended, that player may sacrifice a permanent of their choice. If the player does, put two time counters on Curse of the Cabal.

Reality Strobe

Return target permanent to its owner's hand. Exile Reality Strobe with three time counters on it.
Suspend 3—{2}{U} (Rather than cast this card from your hand, you may pay {2}{U} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Codie, Vociferous Codex

You can't cast permanent spells.
{4}, {T}: Add {W}{U}{B}{R}{G}. When you next cast a spell this turn, exile cards from the top of your library until you exile an instant or sorcery card with lesser mana value. Until end of turn, you may cast that card without paying its mana cost. Put each other card exiled this way on the bottom of your library in a random order.

Weaver of Harmony

Other enchantment creatures you control get +1/+1.
{G}, {T}: Copy target activated or triggered ability you control from an enchantment source. You may choose new targets for the copy. (Mana abilities can't be targeted.)

Aeon Chronicler

Aeon Chronicler's power and toughness are each equal to the number of cards in your hand.
Suspend X—{X}{3}{U}. X can't be 0.
Whenever a time counter is removed from Aeon Chronicler while it's exiled, draw a card.

Sinister Concierge

When Sinister Concierge dies, you may exile it and put three time counters on it. If you do, exile up to one target creature and put three time counters on it. Each card exiled this way that doesn't have suspend gains suspend. (For each card with suspend, its owner removes a time counter from it at the beginning of their upkeep. When the last is removed, they may cast it without paying its mana cost. Those creature spells have haste.)

Jhoira's Timebug

{T}: Choose target permanent you control or suspended card you own. If that permanent or card has a time counter on it, you may remove a time counter from it or put another time counter on it.

Time Warp

Target player takes an extra turn after this one.

Chronozoa

Flying
Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Chronozoa dies, if it had no time counters on it, create two tokens that are copies of it.

Estrid's Invocation

You may have Estrid's Invocation enter as a copy of an enchantment you control, except it has "At the beginning of your upkeep, you may exile this enchantment. If you do, return it to the battlefield under its owner's control."

Ancestral Vision

Suspend 4—{U} (Rather than cast this card from your hand, pay {U} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Target player draws three cards.

Sterling Grove

Other enchantments you control have shroud. (They can't be the targets of spells or abilities.)
{1}, Sacrifice Sterling Grove: Search your library for an enchantment card, reveal it, then shuffle and put that card on top.

Dust of Moments

Choose one —
• Remove two time counters from each permanent and each suspended card.
• Put two time counters on each permanent with a time counter on it and each suspended card.

Mirrormade

You may have Mirrormade enter as a copy of any artifact or enchantment on the battlefield.

Paradox Haze

Enchant player
At the beginning of enchanted player's first upkeep each turn, that player gets an additional upkeep step after this step.

Rousing Refrain

Add {R} for each card in target opponent's hand. Until end of turn, you don't lose this mana as steps and phases end. Exile Rousing Refrain with three time counters on it.
Suspend 3—{1}{R} (Rather than cast this card from your hand, you may pay {1}{R} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Brinelin, the Moon Kraken

When Brinelin, the Moon Kraken enters and whenever you cast a spell with mana value 6 or greater, you may return target nonland permanent to its owner's hand.
Partner (You can have two commanders if both have partner.)

Zaffai, Thunder Conductor

Magecraft — Whenever you cast or copy an instant or sorcery spell, scry 1. If that spell's mana value is 5 or greater, create a 4/4 blue and red Elemental creature token. If that spell's mana value is 10 or greater, Zaffai, Thunder Conductor deals 10 damage to an opponent chosen at random.

Fungal Behemoth

Fungal Behemoth's power and toughness are each equal to the number of +1/+1 counters on creatures you control.
Suspend X—{X}{G}{G}. X can't be 0. (Rather than cast this card from your hand, you may pay {X}{G}{G} and exile it with X time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)
Whenever a time counter is removed from Fungal Behemoth while it's exiled, you may put a +1/+1 counter on target creature.

Deep-Sea Kraken

Deep-Sea Kraken can't be blocked.
Suspend 9—{2}{U} (Rather than cast this card from your hand, you may pay {2}{U} and exile it with nine time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)
Whenever an opponent casts a spell, if Deep-Sea Kraken is suspended, remove a time counter from it.

Rift Elemental

{1}{R}, Remove a time counter from a permanent you control or suspended card you own: Rift Elemental gets +2/+0 until end of turn.

Sphinx of the Second Sun

Flying
At the beginning of each of your postcombat main phases, there is an additional beginning phase after this phase. (The beginning phase includes the untap, upkeep, and draw steps.)

Inevitable Betrayal

Suspend 3—{1}{U}{U} (Rather than cast this card from your hand, pay {1}{U}{U} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search target opponent's library for a creature card and put that card onto the battlefield under your control. Then that player shuffles.

Thousand-Year Storm

Whenever you cast an instant or sorcery spell, copy it for each other instant and sorcery spell you've cast before it this turn. You may choose new targets for the copies.