msem-instigator

Counter target noncreature spell. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Still-Smoke Hunter gets +2/+1 and is a Beast in addition to its other types while it's tapped.
Revive {3}{B} ({3}{B}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost. Activate this ability only any time you could cast a sorcery.)

{2}{G}: Look at the top three cards of your library. You may reveal a creature or Revelation card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Creature cards in your graveyard have revive. The revive cost is equal to their mana cost. (Pay that creature's mana cost, Exile that card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Enchant creature
Enchanted creature's activated abilities can't be activated.
Prevent all damage that would be dealt by enchanted creature.

Menace
Whenever you discard a card, Stillsong Enforcer deals 1 damage to target opponent or planeswalker.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
At the beginning of your end step, each cursed opponent loses 1 life. You gain life equal to the life lost this way.

When Stilthorpe Falconer enters, create a 1/1 white Bird creature token with flying.

Enchant creature
When Sting of the Manticore enters, scry 2.
Enchanted creature gets +1/+0 and has deathtouch.

Deathtouch
Menagerie — When Sting-Hopper enters, if there are five or more creature types among creatures you control, target player reveals their hand. You choose a creature card from it. That player discards that card.

Deathtouch

Menace (This creature can't be blocked except by two or more creatures.)
Sacrifice another creature: Stingbrood Warlord gains deathtouch until end of turn.

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Whenever you cast a spell that doesn't share a color with Stinging Hunter, each opponent loses 1 life.

Flying
Whenever Stingsower attacks, you may pay {3}{B}{B}. If you do, target creature gets -1/-1 for each Insect you control until end of turn.

Choose one or three —
• Target opponent loses 3 life.
• Return target creature card with mana value 3 or less from your graveyard to the battlefield.
• Conjure a card named Fatigue and put it on top of your library. (It's a colorless sorcery that costs {2} with “Draw a card.”)

Flying
Whenever you cast your first spell each turn, add {U}{U}, {U}{R}, or {R}{R}.
Whenever you cast your second spell each turn, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Whenever you cast your third spell each turn, Stirring Igmel deals 3 damage to each opponent.

Create a 2/2 red and white Cat Knight creature token. Creatures you control get +1/+1 and gain haste until end of turn.

Target creature you control gains indestructible until end of turn. Whenever that creature perseveres this turn, create a 2/2 black Zombie creature token. (A creature perseveres when it survives damage.)

Whenever you gain life, each opponent loses 1 life.

Stoic Djinn has flying as long as it has a counter on it.

{T}: Look at the top two cards of your library, then put them back in any order.

When Stoic Observation enters, mill two cards, then you may return a creature card from your graveyard to your hand.
{3}{G}, Exile a creature card from your graveyard: Create a 2/2 green Wolf creature token. You gain 2 life.

Choose two —
• Gain control of target artifact until end of turn. Untap it. It gains haste until end of turn.
• Create a Gold token. (It's an artifact with “Sacrifice this artifact: Add one mana of any color.”)
• Create a Clue token. (It's an artifact with “{2}, Sacrifice this artifact: Draw a card.”)

Choose a nonland card type. Target player reveals their hand. You choose a card of the chosen type from it. That player discards that card.