Rule of Law

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

Erayo's Essence

Whenever an opponent casts their first spell each turn, counter that spell.

Erayo, Soratami Ascendant

Flying
Whenever the fourth spell of a turn is cast, flip Erayo.

Erayo, Soratami Ascendant // Erayo's Essence

Thought Scour

Target player mills two cards.
Draw a card.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Lantern of the Lost

When this artifact enters, exile target card from a graveyard.
{1}, {T}, Exile this artifact: Exile all cards from all graveyards, then draw a card.

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Bone Saw

Equipped creature gets +1/+0.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Plains

Ornithopter

Tocatli Honor Guard

Creatures entering don't cause abilities to trigger.

Mishra's Factory

{T}: Add {C}.
{1}: This land becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Oust

Put target creature into its owner's library second from the top. Its controller gains 3 life.

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform this creature.

Delver of Secrets // Insectile Aberration

Island

Annul

Counter target artifact or enchantment spell.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Magus of the Moat

Wash Away

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Counter target spell [that wasn't cast from its owner's hand].

Ethersworn Canonist

Each player who has cast a nonartifact spell this turn can't cast additional nonartifact spells.