Eidolon of Rhetoric

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

Spell Queller

Flash
Flying
When Spell Queller enters, exile target spell with mana value 4 or less.
When Spell Queller leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.

Nebelgast Herald

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever Nebelgast Herald or another Spirit you control enters, tap target creature an opponent controls.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Mana Confluence

{T}, Pay 1 life: Add one mana of any color.

Tattered Haunter

Flying
Tattered Haunter can block only creatures with flying.

Unsummon

Return target creature to its owner's hand.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Niblis of Frost

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Fogwalker

Skulk (This creature can't be blocked by creatures with greater power.)
When Fogwalker enters, target creature an opponent controls doesn't untap during its controller's next untap step.

Island

Mausoleum Wanderer

Flying
Whenever another Spirit you control enters, Mausoleum Wanderer gets +1/+1 until end of turn.
Sacrifice Mausoleum Wanderer: Counter target instant or sorcery spell unless its controller pays {X}, where X is Mausoleum Wanderer's power.

Remand

Counter target spell. If that spell is countered this way, put it into its owner's hand instead of into that player's graveyard.
Draw a card.

Plains

Spirit of the Labyrinth

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

Hindering Light

Counter target spell that targets you or a permanent you control.
Draw a card.

Repeal

Return target nonland permanent with mana value X to its owner's hand.
Draw a card.