When Agent of Treachery enters the battlefield, gain control of target permanent.

At the beginning of your end step, if you control three or more permanents you don't own, draw three cards.

If a source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

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

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

Bojuka Bog enters tapped.

When Bojuka Bog enters, exile target player's graveyard.

{T}: Add {B}.

Creature tokens you control have haste.

At the beginning of combat on your turn, create a 2/1 blue Phyrexian Myr artifact creature token. Then you may choose a token you control. If you do, each other token you control becomes a copy of that token.

Create a token that's a copy of target creature you control.

Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

{T}: Add {C}.

{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Lands you control have "{T}: Add one mana of any color."

{T}: Add one mana of any color.

{T}: Add {U}.

{T}: Add {B}.

You may have Clever Impersonator enter as a copy of any nonland permanent on the battlefield.

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

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

Sacrifice Commander's Sphere: Draw a card.

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

Counter target spell.

Crumbling Necropolis enters the battlefield tapped.

{T}: Add {U}, {B}, or {R}.

At the beginning of your upkeep, you may have Cryptoplasm become a copy of another target creature, except it has this ability.

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.")

You may have Dack's Duplicate enter the battlefield as a copy of any creature on the battlefield, except it has haste and dethrone. (Whenever it attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)

As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."

Search your library for a card, put that card into your hand, then shuffle.

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

{1}, {T}: Add {U}{B}.

When Dockside Extortionist enters the battlefield, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

You may have Evil Twin enter the battlefield as a copy of any creature on the battlefield, except it has "{U}{B}, {T}: Destroy target creature with the same name as this creature."

{T}: Add one mana of any color that a land an opponent controls could produce.

Create a token that's a copy of target creature you control. If it's your turn, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

{T}: Add one mana of any color that a land an opponent controls could produce.

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

You may have Glasspool Mimic enter the battlefield as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Shore enters the battlefield tapped.

{T}: Add {U}.

{T}: Add {C}.

{B/R}, {T}: Add {B}{B}, {B}{R}, or {R}{R}.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

{1}, {T}: Add {U}{R}.

Whenever an opponent casts a spell, Kaervek the Merciless deals damage equal to that spell's mana value to any target.

Flying

Once during each of your turns, you may cast an instant or sorcery spell from your graveyard. If a spell cast this way would be put into your graveyard, exile it instead.

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.

You may cast spells as though they had flash.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)

Equip {0}

{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.)

Luxury Suite enters the battlefield tapped unless you have two or more opponents.

{T}: Add {B} or {R}.

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

The "legend rule" doesn't apply.

Morphic Pool enters the battlefield tapped unless you have two or more opponents.

{T}: Add {U} or {B}.

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {U}.)

Mystic Sanctuary enters tapped unless you control three or more other Islands.

When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

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

Flash

If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card.

Companion -- Your starting deck contains only cards with odd mana values and land cards. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)

If a source you control with an odd mana value would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

At the beginning of your upkeep, you draw a card and you lose 1 life.

({U/P} can be paid with either {U} or 2 life.)

You may have Phyrexian Metamorph enter the battlefield as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

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

Create a token that's a copy of target creature you control.

Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

{1}, {T}: Add {B}{R}.

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.)

You have no maximum hand size.

{T}: Add {C}.

Counter target spell. Untap up to four lands.

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

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.

{T}: Add {U}.

{T}: Add {R}.

{T}: Add {C}.

{4}, {T}: Target creature can't be blocked this turn.

Choose one or both --

• Create a token that's a copy of target artifact.

• Create a token that's a copy of target creature, except it's an artifact in addition to its other types.

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.)

You may have Sakashima the Impostor enter the battlefield as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."

Flash

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)

You may have Sakashima's Protege enter the battlefield as a copy of any permanent that entered the battlefield this turn.

Choose one. If you control a commander as you cast this spell, you may choose both.

• Target opponent chooses a creature they control. You gain control of it.

• Choose a creature you control. Each other creature you control becomes a copy of that creature until end of turn.

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

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

Flying

When Sower of Temptation enters the battlefield, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

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

As Steam Vents enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Flash

You may have Stunt Double enter the battlefield as a copy of any creature on the battlefield.

Choose one or more --

• Counter target spell.

• Counter target activated or triggered ability.

• Return target nonland permanent to its owner's hand.

• Create a token that's a copy of target creature you control.

• Target player draws a card.

Sulfur Falls enters tapped unless you control an Island or a Mountain.

{T}: Add {U} or {R}.

Return target creature to its owner's hand. You create a token that's a copy of that creature.

({T}: Add {B}.)

({T}: Add {B}.)

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

{T}: Add {C}{C}. Activate only if you control five or more lands.

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 Torrential Gearhulk enters the battlefield, you may cast target instant card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Training Center enters the battlefield tapped unless you have two or more opponents.

{T}: Add {U} or {R}.

Counter target noncreature spell. Untap up to three lands.

You may cast spells as though they had flash.

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.)

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

As Watery Grave enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

At the beginning of each end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)