You may have Sakashima of a Thousand Faces enter the battlefield as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities. The "legend rule" doesn't apply to permanents you control. Partner (You can have two commanders if both have partner.)

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

Imprint — When Chrome Mox enters the battlefield, you may exile a nonartifact, nonland card from your hand. {T}: Add one mana of any of the exiled card's colors.

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

{T}, Sacrifice Lotus Petal: Add one mana of any color.

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you. {T}: Add {C}{C}.

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

If an artifact or creature entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Vigilance Adeline, Resplendent Cathar's power is equal to the number of creatures you control. Whenever you attack, for each opponent, create a 1/1 white Human creature token that's tapped and attacking that player or a planeswalker they control.

Flash Whenever an opponent searches their library, you gain 1 life and draw a card.

Flash Flying If an opponent would search a library, that player searches the top four cards of that library instead.

When Barrin, Tolarian Archmage enters the battlefield, return up to one other target creature or planeswalker to its owner's hand. At the beginning of your end step, if a permanent was put into your hand from the battlefield this turn, draw a card.

Flying Whenever Brago, King Eternal deals combat damage to a player, exile any number of target nonland permanents you control, then return those cards to the battlefield under their owner's control.

Your opponents can't cast spells from anywhere other than their hands.

Vigilance Other creatures you control get +2/+2. Creatures your opponents control get -2/-2.

Indestructible As long as your devotion to white and blue is less than seven, Ephara isn't a creature. At the beginning of each upkeep, if you had another creature enter the battlefield under your control last turn, draw a card.

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Flying When Flickerwisp enters the battlefield, exile another target permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

Whenever a creature you control becomes blocked, you may return it to its owner's hand. Whenever one or more creatures you control deal combat damage to a player, draw a card.

Flying When Guardian of Ghirapur enters the battlefield, exile up to one other target creature or artifact you control. Return it to the battlefield under its owner's control at the beginning of the next end step.

Indestructible As long as your devotion to white is less than five, Heliod isn't a creature. Whenever you gain life, put a +1/+1 counter on target creature or enchantment you control. {1}{W}: Another target creature gains lifelink until end of turn.

Flying Sacrifice Hope of Ghirapur: Until your next turn, target player who was dealt combat damage by Hope of Ghirapur this turn can't cast noncreature spells.

Each opponent can't cast noncreature spells with mana value greater than the number of lands that player controls. Whenever an opponent casts a spell, if no mana was spent to cast it, counter that spell.

Flying Whenever a player casts their second spell each turn, Ledger Shredder connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Flying Activated abilities of creatures your opponents control can't be activated.

Flying {1}, Return a land you control to its owner's hand: Create a 1/1 blue Illusion creature token with flying.

Flying When Mulldrifter enters the battlefield, draw two cards. Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments. Whenever Myrel, Shield of Argive attacks, create X 1/1 colorless Soldier artifact creature tokens, where X is the number of Soldiers you control.

You may have Phantasmal Image enter the battlefield as a copy of any creature on the battlefield, except it's an Illusion in addition to its other types and it has "When this creature becomes the target of a spell or ability, sacrifice it."

When Ranger-Captain of Eos enters the battlefield, you may search your library for a creature card with mana value 1 or less, reveal it, put it into your hand, then shuffle. Sacrifice Ranger-Captain of Eos: Your opponents can't cast noncreature spells this turn.

When Reflector Mage enters the battlefield, return target creature an opponent controls to its owner's hand. That creature's owner can't cast spells with the same name as that creature until your next turn.

As Sanctum Prelate enters the battlefield, choose a number. Noncreature spells with mana value equal to the chosen number can't be cast.

Lifelink (Damage dealt by this creature also causes you to gain that much life.) As long as you have 30 or more life, Serra Ascendant gets +5/+5 and has flying.

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) Skrelv, Defector Mite can't block. {W/P}, {T}: Choose a color. Another target creature you control gains toxic 1 and hexproof from that color until end of turn. It can't be blocked by creatures of that color this turn. ({W/P} can be paid with either {W} or 2 life.)

When Skyclave Apparition enters the battlefield, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less. When Skyclave Apparition leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

Flash Lifelink When Solitude enters the battlefield, exile up to one other target creature. That creature's controller gains life equal to its power. Evoke—Exile a white card from your hand.

When Spirited Companion enters the battlefield, draw a card.

First strike When Thalia's Lancers enters the battlefield, you may search your library for a legendary card, reveal it, put it into your hand, then shuffle.

Indestructible As long as your devotion to blue is less than five, Thassa isn't a creature. At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control. {3}{U}: Tap another target creature.

Flash When Venser, Shaper Savant enters the battlefield, return target spell or permanent to its owner's hand.

Walking Ballista enters the battlefield with X +1/+1 counters on it. {4}: Put a +1/+1 counter on Walking Ballista. Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.

Legendary creatures you control get +2/+1 and have ward {1}. Nonlegendary creatures you control get +1/+1.

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Exile target creature you control, then return that card to the battlefield under your control.

Counter target spell.

Return target nonland permanent you don't control to its owner's hand. Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Exile target creature you control, then return it to the battlefield under its owner's control. Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

If you control a commander, you may cast this spell without paying its mana cost. Counter target noncreature spell.

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost. Counter target spell.

As an additional cost to cast this spell, you may exile any number of white cards from your hand. This spell costs {2} less to cast for each card exiled this way. Exile target artifact, creature, or enchantment with mana value X or less.

({U/P} can be paid with either {U} or 2 life.) Counter target spell with mana value 1.

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Counter target spell. At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Exile target creature. Its controller gains life equal to its power.

{T}: Add {C}. {T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Whenever City of Brass becomes tapped, it deals 1 damage to you. {T}: Add one mana of any color.

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

{T}: Add {W}. {W}, {T}: Prevent the next 2 damage that would be dealt to target legendary creature this turn.

{T}: Add {W}. Channel — {2}{W}, Discard Eiganjo, Seat of the Empire: It deals 4 damage to target attacking or blocking creature. This ability costs {1} less to activate for each legendary creature you control.

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

If Gemstone Caverns is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand. {T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Glacial Fortress enters the battlefield tapped unless you control a Plains or an Island. {T}: Add {W} or {U}.

({T}: Add {W} or {U}.) As Hallowed Fountain enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

({T}: Add {U}.)

{T}, Pay 1 life: Add one mana of any color.

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, 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.

({T}: Add {W}.)

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

({T}: Add {W} or {U}.) Prairie Stream enters the battlefield tapped unless you control two or more basic lands.

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Sea of Clouds enters the battlefield tapped unless you have two or more opponents. {T}: Add {W} or {U}.

({T}: Add {W} or {U}.)

Take an extra turn after this one.

Target player takes an extra turn after this one.