msem-instigator

Reach

Haste
Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{1}{R}: Akaima Rager gets +1/+0 until end of turn.

Whenever you cast a green or blue spell, create a 1/1 green and blue Elemental creature token.
Each Elemental you control enters with an additional +1/+1 counter on it.

Whenever one or more creatures you control attack, create a 1/1 white Soldier creature token that's tapped and attacking.
{3}{W}: Creatures you control get +1/+1 until end of turn.

Flying
Other creatures you control enter with an additional +1/+1 counter on them.
If a spell or ability an opponent controls causes you to discard Sigarda, Dawn of Mercy, put it onto the battlefield instead of putting it into your graveyard.

Creatures you control gain lifelink until end of turn.

Colossal 5—{8}{W}{W} (You may cast this for its colossal cost to have it enter with five +1/+1 counters; or pay {8}{W}{W} as a sorcery: Put five +1/+1 counters on it if it has none.)
Ward {5}
When Hekaton Dismantler's colossal ability puts one or more counters on it, tap each creature you don't control. Those creatures don't untap during their controller's next 100 untap steps.

Enchant creature
When Vampiric Rise enters, fateseal 2. (Look at the top two cards of an opponent's library, then put any number on the bottom and the rest on top in any order.)
Enchanted creature gets +1/+0 and has flying.

Flying, vigilance

When Gharsha, Monstrous Quarry enters, each opponent creates a 1/1 green Elf creature token.
Whenever a creature you control becomes blocked, you may pay {1}. If you do, put a +1/+1 counter on that creature.

Destroy target artifact or enchantment. Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

As Barren Desolation enters, you may pay 2 life. If you don't, Barren Desolation enters tapped.
{T}, Sacrifice Barren Desolation: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

At the beginning of your upkeep, draw a card, then discard a card.
{4}{U}: Tap target creature an opponent controls. It doesn't untap during its controller's next untap step.

At the beginning of your upkeep, draw a card.
At the beginning of your end step, discard a card.

Vision (Whenever this or another creature you control enters, reveal the top card of your library. Then you may put that card into your graveyard.)
Whenever Qilan Seer envisions a creature card, it gets +4/+0 until end of turn.

Counter target noncreature spell unless its controller pays {1}.
If you control a creature with power 4 or greater, counter that spell instead.

Reach
When Risti Watchkeeper enters, rediscover a creature card. (Look at the top card of your library. You may reveal it and put it into your hand if it's a creature card. Otherwise, put it back or into your graveyard.)

When Cathar's Armory enters and at the beginning of your first main phase, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.)
Whenever one or more creatures you control that are enchanted or equipped deal combat damage to a player, draw a card.

Pressure—{2}{U}{U}, Discard your hand. (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Reveal the top seven cards of your library. Put any number of noncreature, nonland cards from among them into your hand and the rest into your graveyard.

[0]: Choose up to one target creature. You may put two +1/+1 counters on it, a +1/+1 counter on it and a loyalty counter on Aoia, Monarch of Beauty, or two loyalty counters on Aoia.
[–2]: Exile target creature, then return it to the battlefield. For each kind of counter on it before it left, put that many of that kind of counter on it.
[–9]: You get an emblem with “If an effect would put one or more counters on a permanent you control, it puts five times that many of those counters on that permanent instead.”
Aoia can be your commander.

When Second-Stage Actress enters, audition for white. (Create a 1/1 Construct Actor creature token, a Scout Role giving 2/3 and vigilance, or a Cleric Role giving 2/2 and lifelink. Roles replace older ones.)
As long as it's your turn, Second-Stage Actress has first strike.

Target player mills two cards. You draw a card and you lose 1 life.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

When Healing Center enters, you gain 2 life.
{T}: Add {C}.

This spell can't be countered.
When Auros enters, it deals damage to any target equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)
{R}, Sacrifice Auros, Discard your hand: Draw three cards.

When Hunting Ground enters, create four 1/1 green Saproling creature tokens.
Whenever a creature you control dies, creatures you control get +1/+1 until end of turn.