Striped Riverwinder

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Cycling {U} ({U}, Discard this card: Draw a card.)

Suffocating Fumes

Creatures your opponents control get -1/-1 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Exhume

Each player puts a creature card from their graveyard onto the battlefield.

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform this creature.

Delver of Secrets // Insectile Aberration

Thought Scour

Target player mills two cards.
Draw a card.

Agony Warp

Target creature gets -3/-0 until end of turn.
Target creature gets -0/-3 until end of turn.

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Troll of Khazad-dûm

This creature can't be blocked except by three or more creatures.
Swampcycling {1} ({1}, Discard this card: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.)

Counterspell

Chainer's Edict

Target player sacrifices a creature of their choice.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Cast Down

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Swamp

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.