msem-instigator

If you would lose the game, instead sacrifice a storied permanent. If you do and your life total is less than 1, it becomes 1.

Search your library for two basic land cards and put them onto the battlefield tapped. Then they become 0/1 green Plant creatures with “This creature can't block” in addition to their other colors, types, and abilities.

Stratospheric Bombardment deals X damage to any target and you gain that much life.

Each player chooses one card in their hand, then discards the rest.

When Strayseeker Ranger enters, search your library for a creature card with mana value 2 or less, reveal it, put it into your hand, then shuffle.
Recite {W}{W} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

Enchant creature
Enchanted creature gets +3/+0 and has first strike.

Strident Retainer's power and toughness are each equal to the number of creatures you control.
Art of war — At the beginning of your end step, if Strident Retainer dealt damage to an opponent this turn, create a 1/1 colorless Samurai creature token.

Choose one —
• Destroy target creature with flying.
• Destroy target artifact.

Players can cast spells only during their own turns.
Each player can't cast more than one spell each turn.

When Student of the Crane enters, create a 1/1 white Bird creature token with flying.

If you've lost life this turn, you may cast this spell as though it had flash.
Return X target cards with different mana values from your graveyard to your hand. Put Studies Past on the bottom of its owner's library.

Investigate ten times. (Create ten colorless Clue artifact tokens with “{2}, Sacrifice this artifact: Draw a card.”)

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever a creature you control becomes renowned, you may have it fight target creature you don't control. (Each deals damage equal to its power to the other.)

Concord — At the beginning of combat on your turn, if there are four or more card types among permanents you control, Sturdyshell Hammerclaw gets +2/+1 and gains trample until end of turn.

When Stygian Leviathan enters, target opponent loses life equal to the number of Curses attached to them and you gain that much life.

Menace (This creature can't be blocked except by two or more creatures.)
Civilized — Whenever Subjugator of Empires attacks, if you control an artifact, a creature, and an enchantment, each opponent discards a card, sacrifices a creature, and loses 3 life.

First strike, vigilance
When Subnautical Legionnaire enters, choose artifact, enchantment, or Merfolk. Exile target nonland permanent you don't control until you control no permanents of the chosen type.

Subway Shambler can't be blocked by creatures with lesser power.
At the beginning of each end step, if you're horrific, put a +1/+1 counter on Subway Shambler. (You're horrific as long as you've sacrificed a permanent or discarded a card this turn.)

Create X 1/1 white Soldier creature tokens, where X is the number of creatures you don't control.

Choose up to one creature. Return the rest to their owners' hands.

Trample, haste
Whenever Sugon, Destruction's Fist deals combat damage to a player, return it to its owner's hand unless you have Sugon deal 5 damage to you.

When Sullen Bonecrusher enters, it deals damage to any target equal to the number of Warriors you control and you gain that much life.

Scry 3, then reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, distribute X +1/+1 counters among any number of target creatures you control, where X is that card's mana value.

Scry X, where X is the highest toughness among creatures you control, then reveal the top card of your library. If it's a creature with mana value X or less, you may put it onto the battlefield.

Counter target creature spell. Create a 2/2 blue Illusion creature token.