Deafening Silence

Each player can't cast more than one noncreature spell each turn.

Aven Mindcensor

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

Archon of Valor's Reach

Flying, vigilance, trample
As this creature enters, choose artifact, enchantment, instant, sorcery, or planeswalker.
Players can't cast spells of the chosen type.

Collector Ouphe

Activated abilities of artifacts can't be activated.

Spirit of the Labyrinth

Each player can't draw more than one card each turn.

Yasharn, Implacable Earth

When Yasharn enters, search your library for a basic Forest card and a basic Plains card, reveal those cards, put them into your hand, then shuffle.
Players can't pay life or sacrifice nonland permanents to cast spells or activate abilities.

Stony Silence

Archon of Emeria

Flying
Each player can't cast more than one spell each turn.
Nonbasic lands your opponents control enter tapped.

Eidolon of Rhetoric

Each player can't cast more than one spell each turn.

Manglehorn

When this creature enters, you may destroy target artifact.
Artifacts your opponents control enter tapped.

Thalia, Heretic Cathar

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

Runic Armasaur

Whenever an opponent activates an ability of a creature or land that isn't a mana ability, you may draw a card.