Trinisphere

As long as this artifact is untapped, each spell that would cost less than three mana to cast costs three mana to cast. (Additional mana in the cost may be paid with any color of mana or colorless mana. For example, a spell that would cost {1}{B} to cast costs {2}{B} to cast instead.)

Damping Engine

A player who controls more permanents than each other player can't play lands or cast artifact, creature, or enchantment spells. That player may sacrifice a permanent of their choice for that player to ignore this effect until end of turn.

Crawlspace

No more than two creatures can attack you each combat.

Ward of Bones

Each opponent who controls more creatures than you can't cast creature spells. The same is true for artifacts and enchantments.
Each opponent who controls more lands than you can't play lands.

Kozilek, the Great Distortion

When you cast this spell, if you have fewer than seven cards in hand, draw cards equal to the difference.
Menace
Discard a card with mana value X: Counter target spell with mana value X.

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Smokestack

At the beginning of your upkeep, you may put a soot counter on this artifact.
At the beginning of each player's upkeep, that player sacrifices a permanent of their choice for each soot counter on this artifact.

Storage Matrix

As long as this artifact is untapped, each player chooses artifact, creature, or land during their untap step. That player can untap only permanents of the chosen type this step.

Void Winnower

Your opponents can't cast spells with even mana values. (Zero is even.)
Your opponents can't block with creatures with even mana values.

Mana Web

Whenever a land an opponent controls is tapped for mana, tap all lands that player controls that could produce any type of mana that land could produce.