Flash Ward {2} Probing Telepathy — Whenever a creature entering under an opponent's control causes a triggered ability of that creature to trigger, you may copy that ability. You may choose new targets for the copy.

When this creature enters, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.) Whenever this creature attacks, you may return another creature you control to its owner's hand. If you do, this creature can't be blocked this turn.

When this creature enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.) {T}: Add one mana of any color.

Shroud (This creature can't be the target of spells or abilities.) Landfall — Whenever a land you control enters, you may switch this creature's power and toughness until end of turn.

{1}{U}: This creature gets +2/-2 until end of turn. At the beginning of your end step, if you haven't cast a spell from your hand this turn, draw a card, then discard a card.

Spells your opponents cast that target Charix cost {2} more to cast. {3}: Charix gets +X/-X until end of turn, where X is the number of Islands you control.

Flash Drag Below — When this creature enters, tap it and up to one target creature an opponent controls. They don't untap during their controllers' next untap steps.

{T}: Untap another target permanent you control. {T}, Collect evidence 3: Tap target creature you don't control. (To collect evidence 3, exile cards with total mana value 3 or greater from your graveyard.)

Landfall — Whenever a land you control enters, target player mills three cards.

{T}: Untap another target permanent you control. {T}: Tap target permanent. Activate only if you control eight or more lands.

Ward {1} Other Frogs you control have ward {1}. When this creature enters, target creature you control can't be blocked this turn. Whenever that creature deals combat damage this turn, you may exile it. If you do, return it to the battlefield under its owner's control.

When this creature enters, return target creature to its owner's hand.

When this creature enters, create two 0/2 blue Illusion creature tokens with "Whenever this token blocks a creature, that creature doesn't untap during its controller's next untap step." This creature has hexproof as long as you control an Illusion.

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.) Channel — {2}{U}, Discard this card: Counter target spell or ability unless its controller pays {3}.

When this creature becomes the target of a spell or ability, sacrifice it. When this creature dies, draw a card.

Ninjutsu {1}{U} ({1}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.) Whenever one or more Ninja or Rogue creatures you control deal combat damage to a player, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Flash Defender

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, target player mills two cards. (They put the top two cards of their library into their graveyard.)

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

Flash When this creature enters, you may exile target historic permanent you control. If you do, return that card to the battlefield under its owner's control at the beginning of the next end step. (Artifacts, legendaries, and Sagas are historic.)

{T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.

Devoid (This card has no color.) Other colorless creatures you control get +0/+1.

{2}{U}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Whenever you cast a creature spell, you may pay {1}. If you do, return target creature to its owner's hand.

{1}, Discard a card: Create a 0/3 blue Crab creature token. Delirium — Crabs you control get +1/+1 as long as there are four or more card types among cards in your graveyard.

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Gift a tapped Fish (You may promise an opponent a gift as you cast this spell. If you do, they create a tapped 1/1 blue Fish creature token before its other effects.) Return target creature an opponent controls to its owner's hand. If the gift was promised, instead return target nonland permanent an opponent controls to its owner's hand.

({T}: Add {U}.)

Create a 0/3 blue Crab creature token. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")