{T}: Add one mana of any color in your commander's color identity.

You may choose not to untap Helm of Possession during your untap step. {2}, {T}, Sacrifice a creature: Gain control of target creature for as long as you control Helm of Possession and Helm of Possession remains tapped.

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy. {3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy. {4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

{T}: Add {U}. {2}{U}: Put an hour counter on Midnight Clock. At the beginning of each upkeep, put an hour counter on Midnight Clock. When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Blue spells you cast cost {1} less to cast.

{T}: Add one mana of any color. {T}: Add three mana of any one color. Activate only if you control three or more lands with the same name.

Sky Diamond enters the battlefield tapped. {T}: Add {U}.

{T}: Add {C}{C}.

At the beginning of your end step, if you didn't activate a loyalty ability of a planeswalker this turn, you lose 2 life. {4}, {T}: For each planeswalker you control, you may activate one of its loyalty abilities once this turn as though none of its loyalty abilities have been activated this turn.

You have no maximum hand size. {T}: Add {C}.

{T}: Add {C}{C}{C}.

Untap all artifacts you control during each other player's untap step.

Enchant permanent You control enchanted permanent.

Enchant creature You control enchanted creature.

Enchant creature You control enchanted creature. Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

As an additional cost to cast this spell, sacrifice a creature. Enchant creature You control enchanted creature. Enchanted creature gets +1/+1.

Whenever you cast a spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Enchant artifact you control At the beginning of your upkeep, create a token that's a copy of enchanted artifact. Then if you control eight or more artifacts with the same name as one another, you win the game.

Whenever an opponent casts their first spell each turn, that player exiles the top card of their library. If it's a nonland card, you may cast it without paying its mana cost.

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.) You control enchanted creature.

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Whenever you cast a noncreature spell, create an X/X blue Shark creature token with flying, where X is that spell's mana value. Cycling {X}{1}{U} ({X}{1}{U}, Discard this card: Draw a card.) When you cycle Shark Typhoon, create an X/X blue Shark creature token with flying.

Enchant creature When Treachery enters the battlefield, untap up to five lands. You control enchanted creature.

Return all attacking creatures to their owner's hand.

For each attacking creature, its owner puts it on the top or bottom of their library.

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep. You draw a card at the beginning of the next turn's upkeep.

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Draw three cards, then put two cards from your hand on top of your library in any order.

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.) Draw a card.

Counter target spell. If an artifact or creature spell is countered this way, put that card onto the battlefield under your control instead of into its owner's graveyard.

Return all creatures to their owners' hands.

Draw two cards, then discard two cards. Untap up to three lands.

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Scry 1. Draw a card.

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

{T}: Add {C}. {1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Castle Vantress enters the battlefield tapped unless you control an Island. {T}: Add {U}. {2}{U}{U}, {T}: Scry 2.

({T}: Add {U}.)

Myriad Landscape enters the battlefield tapped. {T}: Add {C}. {2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

({T}: Add {U}.) Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands. When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

{T}: Add {U}. Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

You have no maximum hand size. {T}: Add {C}.

+1: Draw a card. +1: Untap all creatures you control. −9: Gain control of up to three target creatures.

+1: Look at the top two cards of your library. Put one of them into your graveyard. −3: Return another target nonland permanent to its owner's hand. −8: Each player shuffles their hand and graveyard into their library. You draw seven cards.

+1: Scry 1, then draw a card. −2: Return target creature to its owner's hand. −8: You get an emblem with "Whenever an opponent casts their first spell each turn, counter that spell."

+4: Target player exiles a card from their hand. −3: Exile target permanent. −14: Restart the game, leaving in exile all non-Aura permanent cards exiled with Karn Liberated. Then put those cards onto the battlefield under your control.

+1: Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.") −1: Pay any amount of mana. Look at that many cards from the top of your library, then put one of those cards into your hand and the rest on the bottom of your library in a random order. −7: You get an emblem with "Tap an untapped artifact you control: This emblem deals 1 damage to any target."

Spells your opponents cast that target a creature or planeswalker you control cost {2} more to cast. −2: Create a 2/2 blue Wizard creature token. Draw a card, then discard a card.

+2: Until your next turn, up to one target creature gets -2/-0 and loses flying. −3: Create a 4/4 blue Elemental Bird creature token with flying. −8: You get an emblem with "Islands you control have '{T}: Draw a card.'"

You may activate loyalty abilities of Teferi, Master of Time on any player's turn any time you could cast an instant. +1: Draw a card, then discard a card. −3: Target creature you don't control phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.) −10: Take two extra turns after this one.

Whenever you draw a card, put a loyalty counter on Teferi, Temporal Pilgrim. 0: Draw a card. −2: Create a 2/2 blue Spirit creature token with vigilance and "Whenever you draw a card, put a +1/+1 counter on this creature." −12: Target opponent chooses a permanent they control and returns it to its owner's hand. Then they shuffle each nonland permanent they control into its owner's library.

Return up to three target artifacts and/or creatures to their owners' hands. You may cast a spell with mana value 4 or less from your hand without paying its mana cost.

For each opponent, gain control of target permanent that player controls.

Gain control of target creature with mana value X.

Council's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one. For each money vote, choose a permanent owned by the voter and gain control of it. Exile Expropriate.

Gain control of target artifact or creature. Untap it.

Gain control of X target creatures and/or planeswalkers.

Look at the top three cards of your library, then put them back in any order. You may shuffle. Draw a card.

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Kicker {5} (You may pay an additional {5} as you cast this spell.) Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.