Scheming Symmetry

Choose two target players. Each of them searches their library for a card, then shuffles and puts that card on top.

Cabal Stronghold

{T}: Add {C}.
{3}, {T}: Add {B} for each basic Swamp you control.

Silverclad Ferocidons

Enrage — Whenever this creature is dealt damage, each opponent sacrifices a permanent of their choice.

Roiling Vortex

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

Goblin Chainwhirler

First strike
When this creature enters, it deals 1 damage to each opponent and each creature and planeswalker they control.

Dictate of Erebos

Flash
Whenever a creature you control dies, each opponent sacrifices a creature of their choice.

Underworld Breach

Each nonland card in your graveyard has escape. The escape cost is equal to the card's mana cost plus exile three other cards from your graveyard. (You may cast cards from your graveyard for their escape cost.)
At the beginning of the end step, sacrifice this enchantment.

Revel in Riches

Whenever a creature an opponent controls dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Play with Fire

Play with Fire deals 2 damage to any target. If a player is dealt damage this way, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Legion Loyalist

Haste
Battalion — Whenever this creature and at least two other creatures attack, creatures you control gain first strike and trample until end of turn and can't be blocked by creature tokens this turn.

Canyon Slough

({T}: Add {B} or {R}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Kazarov, Sengir Pureblood

Flying
Whenever a creature an opponent controls is dealt damage, put a +1/+1 counter on Kazarov.
{3}{R}: Kazarov deals 2 damage to target creature.

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice this enchantment.
{B}: This enchantment deals 1 damage to each creature and each player.