Tale's End

Counter target activated ability, triggered ability, or legendary spell.

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.")

Explore the Vastlands

Each player looks at the top five cards of their library and may reveal a land card and/or an instant or sorcery card from among them. Each player puts the cards they revealed this way into their hand and the rest on the bottom of their library in a random order. Each player gains 3 life.

Wandering Archaic

Whenever an opponent casts an instant or sorcery spell, they may pay {2}. If they don't, you may copy that spell. You may choose new targets for the copy.

Wandering Archaic // Explore the Vastlands

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Mox Sapphire

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Ancestral Recall

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Back to Basics

Nonbasic lands don't untap during their controllers' untap steps.

Copy Artifact

You may have Copy Artifact enter as a copy of any artifact on the battlefield, except it's an enchantment in addition to its other types.

Panoptic Mirror

Imprint — {X}, {T}: You may exile an instant or sorcery card with mana value X from your hand.
At the beginning of your upkeep, you may copy a card exiled with Panoptic Mirror. If you do, you may cast the copy without paying its mana cost.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Gitaxian Probe

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

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Island

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Arcane Laboratory

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

Ponder

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

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

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, Soratami Ascendant.

Erayo, Soratami Ascendant // Erayo's Essence

Drift of Phantasms

Defender (This creature can't attack.)
Flying
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Mental Misstep

({U/P} can be paid with either {U} or 2 life.)
Counter target spell with mana value 1.