Enter the Enigma

Target creature can't be blocked this turn.
Draw a card.

Plains

Island

Silent Hallcreeper

Silent Hallcreeper can't be blocked.
Whenever Silent Hallcreeper deals combat damage to a player, choose one that hasn't been chosen —
• Put two +1/+1 counters on Silent Hallcreeper.
• Draw a card.
• Silent Hallcreeper becomes a copy of another target creature you control.

Scorching Dragonfire

Scorching Dragonfire deals 3 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Unable to Scream

Enchant creature
Enchanted creature loses all abilities and is a Toy artifact creature with base power and toughness 0/2 in addition to its other types.
As long as enchanted creature is face down, it can't be turned face up.

Chainsaw

When Chainsaw enters, it deals 3 damage to up to one target creature.
Whenever one or more creatures die, put a rev counter on Chainsaw.
Equipped creature gets +X/+0, where X is the number of rev counters on Chainsaw.
Equip {3}

Fear of Burning Alive

When Fear of Burning Alive enters, it deals 4 damage to each opponent.
Delirium — Whenever a source you control deals noncombat damage to an opponent, if there are four or more card types among cards in your graveyard, Fear of Burning Alive deals that amount of damage to target creature that player controls.

Don't Make a Sound

Counter target spell unless its controller pays {2}. If they do, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Overlord of the Floodpits

Impending 4—{1}{U}{U} (If you cast this spell for its impending cost, it enters with four time counters and isn't a creature until the last is removed. At the beginning of your end step, remove a time counter from it.)
Flying
Whenever Overlord of the Floodpits enters or attacks, draw two cards, then discard a card.

Piggy Bank

When Piggy Bank dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Ragged Playmate

{1}, {T}: Target creature with power 2 or less can't be blocked this turn.

Mountain

Vengeful Possession

Gain control of target creature until end of turn. Untap it. It gains haste until end of turn. You may discard a card. If you do, draw a card.

Attack-in-the-Box

Whenever Attack-in-the-Box attacks, you may have it get +4/+0 until end of turn. If you do, sacrifice it at the beginning of the next end step.

Daggermaw Megalodon

Vigilance
Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Duskmourn's Domination

Enchant creature
You control enchanted creature.
Enchanted creature gets -3/-0 and loses all abilities.

Vanish from Sight

Target nonland permanent's owner puts it on their choice of the top or bottom of their library. Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Hand That Feeds

Delirium — Whenever Hand That Feeds attacks while there are four or more card types among cards in your graveyard, it gets +2/+0 and gains menace until end of turn. (It can't be blocked except by two or more creatures.)

Infernal Phantom

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, Infernal Phantom gets +2/+0 until end of turn.
When Infernal Phantom dies, it deals damage equal to its power to any target.

Trial of Agony

Choose two target creatures controlled by the same opponent. That player chooses one of those creatures. Trial of Agony deals 5 damage to that creature, and the other can't block this turn.

Clockwork Percussionist

Haste
When Clockwork Percussionist dies, exile the top card of your library. You may play it until the end of your next turn.

Arabella, Abandoned Doll

Whenever Arabella, Abandoned Doll attacks, it deals X damage to each opponent and you gain X life, where X is the number of creatures you control with power 2 or less.