msem-instigator

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.

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 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.

When Gendran Hostess enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

When Generous Hermit dies, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Target creature gets +X/+X and gains trample until end of turn.
If you've sacrificed a permanent this turn, draw a card.

Once each turn, you may cast a creature spell with mana value less than or equal to the number of names noted for Genetic Breakthrough without paying its mana cost.
{G}, Sacrifice a nontoken creature with a name not noted for Genetic Breakthrough and note its name: Draw cards equal to the sacrificed creature's power, then discard two cards.

Up to two target creatures each get +X/+X until end of turn. They must be blocked this turn if able.

When Genome Mapper enters, create a Function token with “Create an X/X green Mutant creature token, where X is this spell's mana value.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Reach
Prismatic — Whenever you cast a multicolored spell, you gain 2 life.

Trample

Target creature gets +3/+3 until end of turn.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Giant's Temple enters tapped.
{T}: Add {G}.
{2}{G}, {T}: Target nonland permanent you control becomes a creature with power and toughness equal to its mana value until end of turn. (It loses all other types.)

Equipped creature gets +2/+2 and has trample.
Equip {2}

Choose target creature you control. Mill cards equal to its power, then it fights up to one target creature you don't control.

Enchant creature
Enchanted creature gets +2/+2.
Whenever an enchanted creature you control deals combat damage to a player, you may put a permanent card from your graveyard on top of your library.

Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Put a +1/+1 counter on up to one other target creature you control.
[Lore III] Target creature must be blocked this turn if able.

At the beginning of combat on your turn, create a 1/1 green Elf creature token. That token gains haste until end of turn and attacks this combat if able.
At the beginning of your postcombat main phases, if three or more creatures you control dealt combat damage to a player or planeswalker this turn, add three mana of any one color.

Reach, trample
Deploy 6 (As this enters, you may tap any number of other creatures you control with total power 6 or more.)
When Glaistig of Wild Hunts enters, if it was cast and deployed, untap all lands you control.

Hexproof
You may have Glen Hunter assign its combat damage as though it weren't blocked.

Flash
Reach
Glimmerbark Treant enters with X +1/+1 counters on it.
When Glimmerbark Treant leaves the battlefield, you gain life equal to its power.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
As you reveal a creature card, you may exile it. If you do, you may play that card as long as it is exiled and that spell can't be countered by spells or abilities.