Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

As Arcane Adaptation enters the battlefield, choose a creature type.

Creatures you control are the chosen type in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Arixmethes, Slumbering Isle enters the battlefield tapped with five slumber counters on it.

As long as Arixmethes has a slumber counter on it, it's a land. (It's not a creature.)

Whenever you cast a spell, you may remove a slumber counter from Arixmethes.

{T}: Add {G}{U}.

Trample

Bioessence Hydra enters the battlefield with a +1/+1 counter on it for each loyalty counter on planeswalkers you control.

Whenever one or more loyalty counters are put on planeswalkers you control, put that many +1/+1 counters on Bioessence Hydra.

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

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

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.

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

Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Draw a card.

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.")

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."

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Flash

Emerge {5}{U}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)

When you cast this spell, tap up to four target permanents.

Landfall -- Whenever a land enters the battlefield under your control, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

{T}: Add {C}.

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

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

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

Enchant creature

{U}: Tap enchanted creature.

{U}: Untap enchanted creature.

{T}: Add {G}{U}.

Permanents you control gain hexproof and indestructible until end of turn.

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.

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

{T}: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead.

{3}{G}{G}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)

Trample

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Shroud (This creature can't be the target of spells or abilities.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

When Kiora's Dambreaker enters the battlefield, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

{T}: Untap another target permanent.

Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

-1: Untap target permanent.

+1: Untap up to one target creature and up to one target land.

-2: Reveal the top four cards of your library. You may put a creature card and/or a land card from among them into your hand. Put the rest into your graveyard.

-8: You get an emblem with "Whenever a creature enters the battlefield under your control, you may have it fight target creature." Then create three 8/8 blue Octopus creature tokens.

+1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls.

-1: Draw a card. You may play an additional land this turn.

-5: You get an emblem with "At the beginning of your end step, create a 9/9 blue Kraken creature token."

Whenever Lorthos, the Tidemaker attacks, you may pay {8}. If you do, tap up to eight target permanents. Those permanents don't untap during their controllers' next untap steps.

Flying

When Merfolk Skydiver enters the battlefield, put a +1/+1 counter on target creature you control.

{3}{G}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Target creature you control gets +0/+1 and gains hexproof until end of turn.

Overload {1}{U} (You may cast this spell for its overload cost. If you do, change its text by replacing all instances of "target" with "each.")

{G}: Add one mana of any color.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Enchant creature

{U}: Untap enchanted creature.

{U}: Enchanted creature gains flying until end of turn.

{U}: Enchanted creature gains shroud until end of turn. (It can't be the target of spells or abilities.)

{1}: Enchanted creature gets +1/-1 or -1/+1 until end of turn.

When Pollenbright Druid enters the battlefield, choose one --

• Put a +1/+1 counter on target creature.

• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

{2}: Add one mana of any color.

When Reef Worm dies, create a 3/3 blue Fish creature token with "When this creature dies, create a 6/6 blue Whale creature token with 'When this creature dies, create a 9/9 blue Kraken creature token.'"

Flying, trample

When Roalesk, Apex Hybrid enters the battlefield, put two +1/+1 counters on another target creature you control.

When Roalesk dies, proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Choose one --

• Target creature gets +3/+3 until end of turn.

• Permanents you control gain hexproof until end of turn.

• Return target creature to its owner's hand.

Simic Growth Chamber enters the battlefield tapped.

When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand.

{T}: Add {G}{U}.

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)

When Slinn Voda, the Rising Deep enters the battlefield, if it was kicked, return all creatures to their owners' hands except for Merfolk, Krakens, Leviathans, Octopuses, and Serpents.

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.)

Counter target spell with mana value X.

Counter target noncreature spell unless its controller pays {2}.

Hexproof

Lieutenant -- As long as you control your commander, Stormsurge Kraken gets +2/+2 and has "Whenever Stormsurge Kraken becomes blocked, you may draw two cards."

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

All lands are Islands in addition to their other types.

Creatures without flying or islandwalk can't attack.

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

Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Buyback {5} (You may pay an additional {5} as you cast this spell. If you do, put this card into your hand as it resolves.)

Draw a card.

{T}: Add {C}.

{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.