msem-instigator

When Spiked Burrower dies, if it didn't have a counter on it, return it to the battlefield under your control with a +1/+1 counter or a lifelink counter on it.

Trample
When Spikehorn Behemoth leaves the battlefield or phases out, draw a card.

Once each turn, when one or more cards are put into an opponent's graveyard from their library, you may draw a card.

Gain control of target creature until end of turn. Untap it. Until end of turn, it gets -1/-1 and gains haste.

Reach
Spined Tarantula gets +1/+1 for each creature with flying your opponents control.

When Spinegraft Disabler enters, exile target creature until Spinegraft Disabler leaves the battlefield.

Haste
Ward—Sacrifice a creature.
Spinning Gears Abomination enters with X +1/+1 counters on it.
Spinning Gears Abomination can't attack alone.

Whenever you cast a cryptic spell, put a +1/+1 counter on Spiny Lizard. (Artifacts, enchantments, and modal spells are cryptic.)
When Spiny Lizard dies, you gain life equal to its power.

At the beginning of each player's upkeep, that player discards a card. If that player has no cards in hand, instead they sacrifice a permanent. If they control no permanents, instead they lose the game.

Spire Runner can't be blocked.
Whenever Spire Runner deals combat damage to a player, you may draw a card. If you do, discard a card.

{T}: Add {G}, {W}, or {U}.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {W}, {U} or {B}.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {U}, {B}, or {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {B}, {R}, or {G}.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {R}, {G}, or {W}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Destroy target enchantment. Put a +1/+1 counter on target creature you control.

Enchant creature
Enchanted creature gets +2/+2 and has vigilance.
Sacrifice Spirit Guidance: Exile enchanted creature, then return it to the battlefield under its owner's control.

Lifelink
Revive {W} ({W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Whenever you cast a noncreature spell, you gain 1 life.

Prevent all combat damage that would be dealt to and dealt by target creature this turn.
Inscribe {2}{U} ({2}{U}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Draw two cards, then discard a card.
Whenever you cast an instant or sorcery spell, if Spirit Script is in your graveyard, you may have it become a copy of that spell until end of turn.

Counter target spell. If that spell is countered this way, exile it and its controller's graveyard.

Counter target creature spell.
Permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

When Spirit of Autumn enters, nourish X, where X is the number of creatures you control. (To nourish X, either put X +1/+1 counters on this creature or create X 1/1 white Citizen creature tokens.)

Whenever Spirit of Infamy attacks, 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.)
Spirit of Infamy gets +2/+0 for each bounty counter on it.