msem-instigator

Vigilance
Whenever Underpass Sentinel enters the battlefield or attacks, you may put a +1/+1 counter on another target creature you control without one.
Sacrifice Underpass Sentinel: Embattled creatures you control gain hexproof and indestructible until end of turn. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

Colossal 2—{4}{B} (You may cast this for its colossal cost to have it enter with two +1/+1 counters; or pay {4}{B} as a sorcery: Put two +1/+1 counters on it if it has none.)
Lifelink

Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)
United Patrol can block an additional creature each combat.

{G/W}: If Unlikeliest Heroes doesn't have a +1/+1 counter on it, put a +1/+1 counter on it.
{2}{G/W}{G/W}: If Unlikeliest Heroes has a +1/+1 counter on it and doesn't have vigilance, put two +1/+1 counters and a vigilance counter on it.
{3}{G/W}{G/W}{G/W}: If Unlikeliest Heroes has vigilance and not indestructible, put four +1/+1 counters and an indestructible counter on it.

When Unmasker of Fate's Design enters the battlefield, look at target player's hand. Choose a nonland card from it and exile that card with a puzzle counter on it. As long as that card has a puzzle counter on it, that player may pay {2} and 1 life at any time. If they do, return the exiled card to their hand.

Menace
Foresight — Whenever you draw your second card each turn, target player loses 2 life and you gain 2 life.

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Unruly Magus deals combat damage to a player, draw a card.

Vanishing 5 (This permanent enters the battlefield with five time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
{1}{R}, Remove a time counter from Unstable Magmaling: Flip a coin. If you win the flip, it deals 3 damage to any target.

{T}: Target attacking or blocking creature gets +1/+1 until end of turn.

Ward {1}
Other Scouts you control get +1/+1.
Whenever three or more Scouts you control attack, draw a card.

Rhapsody {4}{R}{W} (Pay {4}{R}{W} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Lifelink, haste

{4}{B}{B}: Return Urchin Defector from your graveyard to the battlefield transformed.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
When Ushi Yun enters the battlefield, create an Idol token.
As long as you're in a renaissance, artifacts you control have “{T}: Draw a card.”

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
When Vaeldan's Liberator dies, you may exile it. If you do, return a permanent card with mana value less than or equal to Vaeldan's Liberator's power from your graveyard to your hand.

Other legendary creatures you control get +1/+1.
At the beginning of your upkeep, you may search your library for a legendary card, reveal that card, and put it into your hand. If you do, you skip your draw step this turn and shuffle.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Whenever Valinov Collector or another artifact enters the battlefield under your control, Valinov Collector deals 2 damage to each opponent and you gain 2 life.

Advance {4}{B}{B} (Cast this for {4}{B}{B} to advance it as it enters. {4}{B}{B}: Advance this as a sorcery.)
Flying
Whenever Valinov Siphoner advances, target player loses 2 life and you gain 2 life.

Advance {3}{R}{W}{B} (Cast this for {3}{R}{W}{B} to advance it as it enters. {3}{R}{W}{B}: Advance this as a sorcery.)
Whenever Valinov Vandal advances, target opponent sacrifices a permanent. Put a +1/+1 counter on Valinov Vandal.

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

When Vasille Rioters enters the battlefield, conjure three cards named Vasille Rioters and shuffle them into your library, then you get a riot counter.
Vasille Rioters gets +1/+1 for each riot counter you have.

Whenever one or more creatures attack you or a planeswalker you control, reveal the top card of your library, then put a -1/-1 counter on each attacking creature with the same mana value as the revealed card.

{T}: Add {G}. Spend this mana only to cast a creature spell or activate an ability of a creature.
At the beginning of combat on your turn, if you control a creature with power 4 or greater, Vassal of the Wild gets +2/+1 and gains vigilance until end of turn.