Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Arms of Hadar

Creatures target player controls get -2/-2 until end of turn.

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.)

Gurmag Angler

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

Blue Elemental Blast

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

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Snow-Covered Island

Contaminated Aquifer

({T}: Add {U} or {B}.)
This land enters tapped.

Unexpected Fangs

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

Ice Tunnel

Diabolic Edict

Target player sacrifices a creature of their choice.

Counterspell

Nihil Spellbomb

{T}, Sacrifice this artifact: Exile target player's graveyard.
When this artifact is put into a graveyard from the battlefield, you may pay {B}. If you do, draw a card.

Augur of Bolas

When this creature enters, look at the top three cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Mental Note

Thought Scour

Target player mills two cards.
Draw a card.

Brainstorm

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

Hydroblast

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

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)