World Queller

At the beginning of your upkeep, you may choose a card type. If you do, each player sacrifices a permanent of their choice of that type.

Aven Mindcensor

Flash
Flying
If an opponent would search a library, that player searches the top four cards of that library instead.

As Meddling Mage enters, choose a nonland card name.
Spells with the chosen name can't be cast.

First strike
Creatures and nonbasic lands your opponents control enter tapped.

Flash
If a nontoken creature would enter and it wasn't cast, exile it instead.

Creature cards in graveyards and libraries can't enter the battlefield.
Players can't cast spells from graveyards or libraries.

Creatures entering don't cause abilities to trigger.

Flying, lifelink
Creatures entering or dying don't cause abilities to trigger.