Act of Treason

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Basri's Aegis

Put a +1/+1 counter on each of up to two target creatures. You may search your library and/or graveyard for a card named Basri, Devoted Paladin, reveal it, and put it into your hand. If you search your library this way, shuffle.

Angelfire Ignition

Put two +1/+1 counters on target creature. It gains vigilance, trample, lifelink, indestructible, and haste until end of turn.
Flashback {2}{R}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Assault Strobe

Target creature gains double strike until end of turn. (It deals both first-strike and regular combat damage.)

Brass's Bounty

For each land you control, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Brightflame

Radiance — Brightflame deals X damage to target creature and each other creature that shares a color with it. You gain life equal to the damage dealt this way.

Cerebral Eruption

Target opponent reveals the top card of their library. Cerebral Eruption deals damage equal to the revealed card's mana value to that player and each creature that player controls. If a land card is revealed this way, return Cerebral Eruption to its owner's hand.

Ajani's Influence

Put two +1/+1 counters on target creature.
Look at the top five cards of your library. You may reveal a white card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Become Brutes

One or two target creatures each gain haste until end of turn. For each of those creatures, create a Monster Role token attached to it. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample.)

Cave-In

You may exile a red card from your hand rather than pay this spell's mana cost.
Cave-In deals 2 damage to each creature and each player.

Abandon the Post

Up to two target creatures can't block this turn.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Bonus Round

Until end of turn, whenever a player casts an instant or sorcery spell, that player copies it and may choose new targets for the copy.

Chain Lightning

Chain Lightning deals 3 damage to any target. Then that player or that permanent's controller may pay {R}{R}. If the player does, they may copy this spell and may choose a new target for that copy.

Arm the Cathars

Until end of turn, target creature gets +3/+3, up to one other target creature gets +2/+2, and up to one other target creature gets +1/+1. Those creatures gain vigilance until end of turn.

Academic Probation

Choose one —
• Choose a nonland card name. Opponents can't cast spells with the chosen name until your next turn.
• Choose target nonland permanent. Until your next turn, it can't attack or block, and its activated abilities can't be activated.

Call Forth the Tempest

Cascade, cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order. Then do it again.)
Call Forth the Tempest deals damage to each creature your opponents control equal to the total mana value of other spells you've cast this turn.

Blinding Flare

Strive — This spell costs {R} more to cast for each target beyond the first.
Any number of target creatures can't block this turn.

Aisha of Sparks and Smoke

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{R/W}: Aisha of Sparks and Smoke gains first strike until end of turn.
Whenever Aisha deals combat damage, you may cast a sorcery spell from your hand with mana value less than or equal to that damage without paying its mana cost.

By Invitation Only

Choose a number between 0 and 13. Each player sacrifices that many creatures.

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Apex of Power

Exile the top seven cards of your library. Until end of turn, you may cast spells from among them.
If this spell was cast from your hand, add ten mana of any one color.