msem-instigator

At the beginning of your end step, amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever a creature dies, add a quest counter.
1, 2 — Target player loses 1 life and you gain 1 life.
3 — Put target creature card from a graveyard onto the battlefield under your control.
​

Choose a creature type. Reveal cards from the top of your library until you reveal a card of the chosen type. Put that card into your hand and the rest on the bottom of your library in a random order.

Gathering Beacon enters tapped.
{T}: Add {G}.
{2}, {T}, Sacrifice Gathering Beacon: Choose a creature or planeswalker type, then reveal the top five cards of your library. You may put a card of the chosen type into your hand, then put the rest on the bottom in any order.

Create three 1/1 blue Advisor creature tokens.
Monument {2}{G}{U} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

When Gau Ding Soulhoard dies, create X 1/1 colorless Spirit creature tokens, where X is its power.
Scavenge {4}{B} ({4}{B}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

[+1]: Creatures you control get +0/+1 until your next upkeep. Untap those creatures.
[–2]: Put target tapped creature into its owner's library third from the top.
[–7]: You get an emblem with “Whenever a nonland permanent you control is put into a graveyard from the battlefield, each opponent sacrifices a nonland permanent.”

First strike
When Gavis's Dragoons enters, exile another target creature until Gavis's Dragoons leaves the battlefield.
Spells with the same name as the exiled card can't be cast (as long as this creature is on the battlefield).

Trample
Whenever Gavony Cavaliers enters or attacks, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.)
Creatures you control that are enchanted or equipped have trample.

Search your library for three land cards with different names, reveal them, then shuffle. Put one of those cards onto the battlefield, one into your hand, and one into your graveyard.

Prevent all combat damage target creature would deal this turn. You gain life equal to that creature's power.

Enchant opponent
Enchanted player plays with the top card of their library revealed.
Whenever enchanted player casts a spell, you may have them mill a card.

Flying
{1}, Sacrifice Gearcraft Observer: Look at target player's hand. Draw a card.

{1}{U}{R}, {T}: Create a token that's a copy of another target creature, except it's an artifact in addition to its other types and has “Whenever this creature is dealt damage, destroy it.”

Vigilance
When this creature transforms into Geist Whisperer, create two 1/1 white Spirit creature tokens with flying.
At the beginning of your end step, untap all Spirits and creatures with flying you control.

Vigilance
{T}: Target instant or sorcery card in your graveyard with mana value 3 or less gains flashback {0} until end of turn. Activate only as a sorcery. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

When Geistmage's Grimoire enters, draw two cards.
{4}{U}, {T}: Target creature can't be blocked this turn.

When Gemcrusher Turtle enters, choose one —
• Destroy target artifact.
• Gemcrusher Turtle fights up to one target creature.

When you cast a creature spell, sacrifice Gemini Cast. If you do, create a token that's a copy of that spell, except the token isn't legendary.

When Gemplate Golem enters or dies, put a +1/+1 counter on target creature you control.

Flying
When Gemscale Drake enters, create a Treasure token.
Whenever Gemscale Drake deals combat damage to a player, scry 1. If you control three or more artifacts, draw a card instead.

Whenever you cast a spell with mana value 5 or greater, create an X/1 red Mutant creature token with trample and haste, where X is that spell's mana value. Exile that token at the beginning of the next end step.

When GenTech Architect enters, create a Function token with “Put two +1/+1 counters on a creature you control.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

When GenTech Assistants enters, create an X/X green Mutant creature token.

Once during each of your turns, when you sacrifice a permanent, you may have target opponent lose 3 life unless they sacrifice a nonland permanent or discard a card.