Doomwake Giant

Constellation — Whenever this creature or another enchantment you control enters, creatures your opponents control get -1/-1 until end of turn.

Steel Hellkite

Flying
{2}: This creature gets +1/+0 until end of turn.
{X}: Destroy each nonland permanent with mana value X whose controller was dealt combat damage by this creature this turn. Activate only once each turn.

Aetherize

Return all attacking creatures to their owner's hand.

Impending Flux

Paradox — Impending Flux deals X damage to each opponent and each creature they control, where X is 1 plus the number of spells you've cast from anywhere other than your hand this turn.
Foretell {1}{R}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Hurkyl's Recall

Return all artifacts target player owns to their hand.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

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.

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Curse of Death's Hold

Enchant player
Creatures enchanted player controls get -1/-1.

Ezuri's Predation

For each creature your opponents control, create a 4/4 green Phyrexian Beast creature token. Each of those tokens fights a different one of those creatures.

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Mob Verdict

Secret council — Each player secretly votes for another player, then those votes are revealed. For each vote an opponent received, Mob Verdict deals 2 damage to that player and each creature that player controls. For each vote you received, draw a card.

Dwarven Catapult

Dwarven Catapult deals X damage divided evenly, rounded down, among all creatures target opponent controls.

Neutralize the Guards

Creatures target opponent controls get -1/-1 until end of turn. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Riveteers Confluence

Choose three. You may choose the same mode more than once.
• You draw a card and you lose 1 life.
• Riveteers Confluence deals 1 damage to each creature and planeswalker you don't control.
• You may put a land card from your hand or graveyard onto the battlefield tapped.

Wail of War

Choose one —
• Creatures target opponent controls get -1/-1 until end of turn.
• Return up to two target creature cards from your graveyard to your hand.

Festering March

Creatures your opponents control get -1/-1 until end of turn. Exile Festering March with three time counters on it.
Suspend 3—{2}{B} (Rather than cast this card from your hand, you may pay {2}{B} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)