Negate

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Aetherize

Return all attacking creatures to their owner's hand.

Hydrolash

Attacking creatures get -2/-0 until end of turn.
Draw a card.

Dissipate

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Opportunity

Downsize

Target creature you don't control gets -4/-0 until end of turn.
Overload {2}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

Flashfreeze

Prism Ring

As Prism Ring enters, choose a color.
Whenever you cast a spell of the chosen color, you gain 1 life.

Island

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Counterspell

Essence Scatter

Artificer's Epiphany

Draw two cards. If you control no artifacts, discard a card.

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.