High Alert

Each creature you control assigns combat damage equal to its toughness rather than its power.
Creatures you control can attack as though they didn't have defender.
{2}{W}{U}: Untap target creature.

Scuttletide

{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.

Island

Charix, the Raging Isle

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

Shields of Velis Vel

Changeling (This card is every creature type.)
Creatures target player controls get +0/+1 and gain all creature types until end of turn.

Faithful Mending

You gain 2 life, draw two cards, then discard two cards.
Flashback {1}{W}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Irrigated Farmland

({T}: Add {W} or {U}.)
Irrigated Farmland enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Port Town

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.

Mishra's Bauble

{T}, Sacrifice Mishra's Bauble: Look at the top card of target player's library. Draw a card at the beginning of the next turn's upkeep.

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Hard Evidence

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

Plains

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Huatli, the Sun's Heart

Each creature you control assigns combat damage equal to its toughness rather than its power.
−3: You gain life equal to the greatest toughness among creatures you control.