Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

O-Kagachi, Vengeful Kami

Flying, trample
Whenever O-Kagachi, Vengeful Kami deals combat damage to a player, if that player attacked you during their last turn, exile target nonland permanent that player controls.

Congregate

Target player gains 2 life for each creature on the battlefield.

Spell Swindle

Counter target spell. Create X Treasure tokens, where X is that spell's mana value. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Plasm Capture

Counter target spell. At the beginning of your next first main phase, add X mana in any combination of colors, where X is that spell's mana value.

Imp's Mischief

Change the target of target spell with a single target. You lose life equal to that spell's mana value.

Pariah's Shield

All damage that would be dealt to you is dealt to equipped creature instead.
Equip {3}

Progenitus

Protection from everything
If Progenitus would be put into a graveyard from anywhere, reveal Progenitus and shuffle it into its owner's library instead.

Riot Control

You gain 1 life for each creature your opponents control. Prevent all damage that would be dealt to you this turn.

Valor Made Real

Target creature can block any number of creatures this turn.

Moment's Peace

Prevent all combat damage that would be dealt this turn.
Flashback {2}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dawn Charm

Choose one —
• Prevent all combat damage that would be dealt this turn.
• Regenerate target creature.
• Counter target spell that targets you.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Respite

Prevent all combat damage that would be dealt this turn. You gain 1 life for each attacking creature.

Spark Double

You may have Spark Double enter as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Aetherize

Return all attacking creatures to their owner's hand.

Entangler

Enchant creature
Enchanted creature can block any number of creatures.

Take the Bait

Cast this spell only during an opponent's turn and only during combat.
Prevent all combat damage that would be dealt to you and planeswalkers you control this turn. Untap all attacking creatures and goad them. After this phase, there is an additional combat phase.

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Simulacrum

You gain life equal to the damage dealt to you this turn. Simulacrum deals damage to target creature you control equal to the damage dealt to you this turn.

Darkness

Prevent all combat damage that would be dealt this turn.

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Pariah

Enchant creature
All damage that would be dealt to you is dealt to enchanted creature instead.

Ethereal Haze

Prevent all damage that would be dealt by creatures this turn.

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Master Warcraft

Cast this spell only before attackers are declared.
You choose which creatures attack this turn.
You choose which creatures block this turn and how those creatures block.