Rug of Smothering

Flying
Whenever a player casts a spell, they lose 1 life for each spell they've cast this turn.

Basilisk Collar

Equipped creature has deathtouch and lifelink.
Equip {2}

Shadow in the Warp

The first creature spell you cast each turn costs {2} less to cast.
Whenever an opponent casts their first noncreature spell each turn, Shadow in the Warp deals 2 damage to that player.

Pyrostatic Pillar

Whenever a player casts a spell with mana value 3 or less, Pyrostatic Pillar deals 2 damage to that player.

Jiwari, the Earth Aflame

{X}{R}, {T}: Jiwari, the Earth Aflame deals X damage to target creature without flying.
Channel — {X}{R}{R}{R}, Discard Jiwari: Jiwari deals X damage to each creature without flying.

Rocco, Cabaretti Caterer

When Rocco, Cabaretti Caterer enters, if you cast it, you may search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Minsc, Beloved Ranger

When Minsc, Beloved Ranger enters, create Boo, a legendary 1/1 red Hamster creature token with trample and haste.
{X}: Until end of turn, target creature you control has base power and toughness X/X and becomes a Giant in addition to its other types. Activate only as a sorcery.

Mirrorworks

Whenever another nontoken artifact you control enters, you may pay {2}. If you do, create a token that's a copy of that artifact.

Touch the Spirit Realm

When Touch the Spirit Realm enters, exile up to one target artifact or creature until Touch the Spirit Realm leaves the battlefield.
Channel — {1}{W}, Discard Touch the Spirit Realm: Exile target artifact or creature. Return it to the battlefield under its owner's control at the beginning of the next end step.

Astral Drift

Whenever you cycle Astral Drift or cycle another card while Astral Drift is on the battlefield, you may exile target creature. If you do, return that card to the battlefield under its owner's control at the beginning of the next end step.
Cycling {2}{W} ({2}{W}, Discard this card: Draw a card.)

Scytheclaw Raptor

Whenever a player casts a spell, if it's not their turn, Scytheclaw Raptor deals 4 damage to them.

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

Eidolon of the Great Revel

Whenever a player casts a spell with mana value 3 or less, Eidolon of the Great Revel deals 2 damage to that player.

Decree of Justice

Create X 4/4 white Angel creature tokens with flying.
Cycling {2}{W} ({2}{W}, Discard this card: Draw a card.)
When you cycle Decree of Justice, you may pay {X}. If you do, create X 1/1 white Soldier creature tokens.

Razorkin Needlehead

Razorkin Needlehead has first strike during your turn.
Whenever an opponent draws a card, Razorkin Needlehead deals 1 damage to them.

Shigeki, Jukai Visionary

{1}{G}, {T}, Return Shigeki, Jukai Visionary to its owner's hand: Reveal the top four cards of your library. You may put a land card from among them onto the battlefield tapped. Put the rest into your graveyard.
Channel — {X}{X}{G}{G}, Discard Shigeki: Return X target nonlegendary cards from your graveyard to your hand.

Altanak, the Thrice-Called

Trample
Whenever Altanak, the Thrice-Called becomes the target of a spell or ability an opponent controls, draw a card.
{1}{G}, Discard Altanak, the Thrice-Called: Return target land card from your graveyard to the battlefield tapped.

Cindervines

Whenever an opponent casts a noncreature spell, Cindervines deals 1 damage to that player.
{1}, Sacrifice Cindervines: Destroy target artifact or enchantment. Cindervines deals 2 damage to that permanent's controller.

Quakefoot Cyclops

When Quakefoot Cyclops enters, up to two target creatures can't block this turn.
Cycling {1}{R} ({1}{R}, Discard this card: Draw a card.)
When you cycle Quakefoot Cyclops, target creature can't block this turn.

Baird, Steward of Argive

Vigilance
Creatures can't attack you or planeswalkers you control unless their controller pays {1} for each of those creatures.

Rampaging War Mammoth

Trample
Cycling {X}{2}{R} ({X}{2}{R}, Discard this card: Draw a card.)
When you cycle Rampaging War Mammoth, destroy up to X target artifacts.

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Ruric Thar, the Unbowed

Vigilance, reach
Ruric Thar, the Unbowed attacks each combat if able.
Whenever a player casts a noncreature spell, Ruric Thar deals 6 damage to that player.

Careful Cultivation

Enchant artifact or creature
As long as enchanted permanent is a creature, it gets +1/+3 and has reach and "{T}: Add {G}{G}."
Channel — {1}{G}, Discard Careful Cultivation: Create a 1/1 green Human Monk creature token with "{T}: Add {G}."

Roiling Vortex

At the beginning of each player's upkeep, Roiling Vortex deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, Roiling Vortex deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.

Greater Tanuki

Trample
Channel — {2}{G}, Discard Greater Tanuki: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Yidaro, Wandering Monster

Trample, haste
Cycling {1}{R}
When you cycle Yidaro, Wandering Monster, shuffle it into your library from your graveyard. If you've cycled a card named Yidaro, Wandering Monster four or more times this game, put it onto the battlefield from your graveyard instead. (Do this before you draw.)

Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Beckoning Will-o'-Wisp

Flying
Lure the Unwary — At the beginning of combat on your turn, choose an opponent.
Creatures attacking the last chosen player get +1/+0.

Springheart Nantuko

Bestow {1}{G}
Enchanted creature gets +1/+1.
Landfall — Whenever a land you control enters, you may pay {1}{G} if Springheart Nantuko is attached to a creature you control. If you do, create a token that's a copy of that creature. If you didn't create a token this way, create a 1/1 green Insect creature token.

Splendor Mare

Lifelink
Cycling {1}{W} ({1}{W}, Discard this card: Draw a card.)
When you cycle Splendor Mare, put a lifelink counter on target creature you control.

Astral Slide

Whenever a player cycles a card, you may exile target creature. If you do, return that card to the battlefield under its owner's control at the beginning of the next end step.

Sculpting Steel

You may have Sculpting Steel enter as a copy of any artifact on the battlefield.