When Breaching Leviathan enters the battlefield, if you cast it from your hand, tap all nonblue creatures. Those creatures don't untap during their controllers' next untap steps.

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.

Return all attacking creatures to their owner's hand.

As Ixidron enters the battlefield, turn all other nontoken creatures face down. (They're 2/2 creatures.) Ixidron's power and toughness are each equal to the number of face-down creatures on the battlefield.

When Scourge of Fleets enters the battlefield, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Creatures you control have flying. Creatures your opponents control lose flying and can't have or gain flying.

If you control two or more other lands, Hall of Storm Giants enters the battlefield tapped. {T}: Add {U}. {5}{U}: Until end of turn, Hall of Storm Giants becomes a 7/7 blue Giant creature with ward {3}. It's still a land. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

You may play an additional land on each of your turns. Landfall — Whenever a land enters the battlefield under your control, you may draw a card.

When Coiling Oracle enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card. Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.) Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

This spell can't be countered. You have no maximum hand size. Whenever an opponent casts a noncreature spell, draw a card. Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

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."

This spell costs {X} less to cast, where X is the greatest power among creatures you control. {T}: Add {G}{G}. You gain 2 life. Whenever a nontoken creature enters the battlefield under your control, put a +1/+1 counter on it and draw a card.

Draw three cards. Then discard two cards unless you discard a basic land card.

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

{T}: Add {C}. {2}, {T}, Sacrifice a Desert: Exile all graveyards.

({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.

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

Dreamroot Cascade enters the battlefield tapped unless you control two or more other lands. {T}: Add {G} or {U}.

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

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

({T}: Add {G}.)

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island. {T}: Add {G} or {U}.

({T}: Add {U}.)

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}.

Temple of Mystery enters the battlefield tapped. When Temple of Mystery enters the battlefield, scry 1. {T}: Add {G} or {U}.

As Vineglimmer Snarl enters the battlefield, you may reveal a Forest or Island card from your hand. If you don't, Vineglimmer Snarl enters the battlefield tapped. {T}: Add {G} or {U}.

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.

Counter target spell.

Creatures you control have hexproof. {1}{G}: Regenerate target creature. (The next time it would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

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

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}.

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If you control a creature with power 4 or greater, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

As an additional cost to cast this spell, sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

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

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

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

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

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

Search your library for a Forest card, put it onto the battlefield, then shuffle.

You may play lands from your graveyard. {T}: Choose target nonland permanent card in your graveyard. If you haven't cast a spell this turn, you may cast that card. If you do, you can't cast additional spells this turn. Activate only as a sorcery.

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

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Flash This spell can't be countered. Whenever you cast a spell, choose up to one — • Return target spell you don't control to its owner's hand. • Return target nonland permanent to its owner's hand.

{G}, {T}: You may put a creature card from your hand onto the battlefield.

Draw a card. You may put a land card from your hand onto the battlefield.

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

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.

This spell can't be countered. At the beginning of each upkeep, create a 3/3 blue Serpent creature token named Koma's Coil. Sacrifice another Serpent: Choose one — • Tap target permanent. Its activated abilities can't be activated this turn. • Koma, Cosmos Serpent gains indestructible until end of turn.

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

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

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

Whenever a creature enters the battlefield under your control, draw a card if its power is 3 or greater. Otherwise, put two +1/+1 counters on it.