Douse

Shifting Sky

As this enchantment enters, choose a color.
All nonland permanents are the chosen color.

Flash Flood

Choose one —
• Destroy target red permanent.
• Return target Mountain to its owner's hand.

Blind Seer

{1}{U}: Target spell or permanent becomes the color of your choice until end of turn.

Neutralizing Blast

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Kormus Bell

All Swamps are 1/1 black creatures that are still lands.

Mana Maze

Players can't cast spells that share a color with the spell most recently cast this turn.

Shimmer

As this enchantment enters, choose a land type.
Each land of the chosen type has phasing. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)

High Seas

Red creature spells and green creature spells cost {1} more to cast.

Mourner's Shield

Imprint — When this artifact enters, you may exile target card from a graveyard.
{2}, {T}: Prevent all damage that would be dealt this turn by a source of your choice that shares a color with the exiled card.

Floodgate

Defender
When this creature has flying, sacrifice it.
When this creature leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Hunting Drake

Flying
When this creature enters, put target red or green creature on top of its owner's library.

Breath of Dreams

Cumulative upkeep {U} (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.)
Green creatures have "Cumulative upkeep {1}."

Surge Mare

This creature can't be blocked by green creatures.
Whenever this creature deals damage to an opponent, you may draw a card. If you do, discard a card.
{1}{U}: This creature gets +2/-2 until end of turn.

Chill

Insight

Whenever an opponent casts a green spell, you draw a card.

Chaos Wand

{4}, {T}: Target opponent exiles cards from the top of their library until they exile an instant or sorcery card. You may cast that card without paying its mana cost. Then put the exiled cards that weren't cast this way on the bottom of that library in a random order.

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Homarid Shaman

Tempest Djinn

Flying
This creature gets +1/+0 for each basic Island you control.

Inundate

Return all nonblue creatures to their owners' hands.

Volcanic Eruption

Destroy X target Mountains. Volcanic Eruption deals damage to each creature and each player equal to the number of Mountains put into a graveyard this way.

Tidal Control

Cumulative upkeep {2} (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.)
Pay 2 life or {2}: Counter target red or green spell. Any player may activate this ability.

Distorting Lens

{T}: Target permanent becomes the color of your choice until end of turn.

Dream Tides

Creatures don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player may choose any number of tapped nongreen creatures they control and pay {2} for each creature chosen this way. If the player does, untap those creatures.

Wrath of Marit Lage

When this enchantment enters, tap all red creatures.
Red creatures don't untap during their controllers' untap steps.

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.