msem-instigator

Destroy target creature, enchantment, or planeswalker. Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

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.)

At the beginning of your upkeep, return target creature or enchantment card with mana value 2 or less from your graveyard to the battlefield.
At the beginning of your end step, you may sacrifice a creature or enchantment. If you do, draw a card.

Ward {1}
Streetslipper can't be blocked.
Whenever you foretell a card or cast a foretold spell, put a +1/+1 counter on Streetslipper.

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

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Whenever this creature attacks, up to two target Citizens or Peasants each get +1/+0 and gain trample until end of turn.

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.

Kicker—Sacrifice an artifact. (You may sacrifice an artifact in addition to any other costs as you cast this spell.)
Target creature's owner puts it on the top or bottom of their library. If this spell was kicked, draw a card.

Tap up to two target creatures. Those creatures don't untap during their controllers' next untap steps. Scry 1.

As an additional cost to cast this spell, put a -1/-1 counter on a creature you control.
Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

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.

Flying
Suisei the Southern Star gets +1/+1 for each comet counter you have.
Whenever you cast an instant or sorcery spell with mana value greater than the number of comet counters you have, you may pay {R}. If you do, return Suisei from your graveyard to the battlefield, then you get a comet counter.

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

Reveal the top four cards of your library. Put up to two creature cards with mana value 3 or less from among them onto the battlefield and the rest into your graveyard.
Prophecy {2}{G} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

You may have Sun Yun enter as a copy of any creature on the battlefield, except her name is Sun Yun, Master of Man, she's legendary in addition to her other types, and she has “{2}{U}: Exile Sun Yun, then return her to the battlefield under her owner's control.”

If a creature entering the battlefield under your control causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
{1}{U}, {T}: Exile another target creature. Return it to the battlefield under its owner's control at the beginning of the next end step.

When Sun-Blessed Hoplite enters, target creature you control gets +X/+X until end of turn, where X is your devotion to white. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)

Vanguard — Whenever a creature you control attacks alone, you may cast a spell with mana value 3 or less from your hand without paying its mana cost.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{3}{R}{W}: Creatures you control gain flying and haste until end of turn.

Whenever a land you control enters or a land card is put into your graveyard from anywhere, create a 0/1 green Plant creature token.
{3}{G}{G}: Put a +1/+1 counter on each other creature you control.

Create two 2/2 white Griffin creature tokens with flying. If you control a legendary creature, create three of those tokens instead.

Primal {1}{W}{W} (During your turn, you may cast this spell for {1}{W}{W} instead of playing a land.)
Double strike
When Sunken Slasher enters, if you didn't play a land this turn, put a +1/+1 counter on it.

When Sunset Cliffs Lawman enters, you may post a bounty on target creature. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)