Vodalian Mage

{U}, {T}: Counter target spell unless its controller pays {1}.

Ertai, Wizard Adept

Disruptive Pitmage

{T}: Counter target spell unless its controller pays {1}.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Ertai, the Corrupted

{U}, {T}, Sacrifice a creature or enchantment: Counter target spell.

Presence of the Master

Whenever a player casts an enchantment spell, counter it.

Mundungu

{T}: Counter target spell unless its controller pays {1} and 1 life.

Daring Apprentice

{T}, Sacrifice Daring Apprentice: Counter target spell.

Disruptive Student

{T}: Counter target spell unless its controller pays {1}.

Ghost-Lit Warder

{3}{U}, {T}: Counter target spell unless its controller pays {2}.
Channel — {3}{U}, Discard Ghost-Lit Warder: Counter target spell unless its controller pays {4}.

Psychic Trance

Until end of turn, Wizards you control gain "{T}: Counter target spell."

Patron Wizard

Tap an untapped Wizard you control: Counter target spell unless its controller pays {1}.