msem-instigator

{3}{B}: You mill two cards. Each opponent loses 2 life.
{1}{G}: You may put a land card from your hand or graveyard onto the battlefield tapped.

Prowess
Whenever you cast a noncreature spell, you may choose target permanent with one or more time counters on it, then put a time counter on it or remove a time counter from it.

Whenever one or more nontoken Merfolk you control attack, create a 2/1 red Merfolk creature token.

Whenever you cast a spell with mana value greater than Script Jockey's power, put a +1/+1 counter on Script Jockey.

Settlement Scout can't be blocked if you control an attacking creature with greater power than it.
Revive {3}{R} ({3}{R}, 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.)

When Shapur, the Fifth Shah enters, exile target instant or sorcery card from your graveyard. Until end of turn, you may cast that card. If that spell would be put into a graveyard, exile it instead.
Monument {4}{R} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Vanguard — Whenever a creature you control attacks alone, Shocking Ewe deals 2 damage to defending player.

Whenever Single-Minded Mob becomes untapped, it gets +2/+2 until end of turn.

{1}{R}: Target creature can't block Slippery Salamander this turn.

Whenever you cast an instant, sorcery, or Wizard spell, Slipsand Runemage deals 1 damage to any target.

Whenever Slithering Eyes deals damage to a player, you may exile that many cards from the top of your library. Until the end of your next turn, you may play those cards.

Flying
{R}: Slyten Ignitor gets +1/+0 until end of turn.

Prowess
Whenever you cast a noncreature spell, you may pay {R}. If you do, 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.)

When Speed Reader enters, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Add {R}{R}.

Flash
When Splitting Image enters, you may pay {2} any number of times. Whenever you do, copy target spell. You may reselect modes and choose new targets for the copies.

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.)

Stormbred Elemental gets +1/+1 as long as you control an Island.
{U}: Stormbred Elemental gains flying until end of turn.

Whenever another Warrior creature you control attacks, you may return Stubborn Blademate from your graveyard to the battlefield tapped and attacking. If you do, sacrifice it at end of combat.

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, Substack Sniper deals 1 damage to you and to each cursed opponent.

At the beginning of your upkeep, Suitor of the Sea deals 1 damage to each player.

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.)
{5}{R}: Sullivan's Courier gets +2/+2 until end of turn.

{2/R}: Suraj Outrider gets +1/+0 until end of turn.

Prowess
Whenever you cast a noncreature spell, Surestrike Elite gains first strike until end of turn.

First strike
Tesqua Cohort enters with a +1/+1 counter on it if you control another creature with a +1/+1 counter on it.

Flying, haste
Thermal Surger can't block.
When Thermal Surger enters, you may sacrifice a land or exile a land card from your graveyard. If you do, put a +1/+1 counter on Thermal Surger.