msem-instigator

As Game Trail enters, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters tapped.
{T}: Add {R} or {G}.

First strike
Noncreature spells with mana value 3 or greater cost {1} more to cast.
Creatures with mana value 3 or greater enter tapped.

First strike
Creatures with power greater than Gao'Wu, Master Soothsayer's power can't attack.

As long as you control five or more creatures, if you would create a token, you may instead create Hu Li, a legendary 4/4 white Fox Spirit creature token with flying and lifelink.

Once each turn, when you cast a creature spell, you may copy it for each other spell you cast this turn. (A copy of a creature spell becomes a token.)
Whenever Garragrok, Horde Tyrant attacks, add {R}{R}{G}{G}. Until end of turn, you don't lose this mana as steps and phases end.

Vigilance
Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Whenever an opponent attacks you, create a tapped 1/1 white Soldier creature token with melee. Exile that token at the beginning of your next end step.

First mate—Your starting deck contains no creature cards. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Prowess
Whenever Garth attacks, look at the top card of your library. If it's an instant or sorcery card, you may cast it. (You still pay its costs.)

{1}, Sacrifice Gasoline Canister: It deals 1 damage to any target. If a creature or planeswalker dealt damage this way would die this turn, exile it instead.

Whenever another creature you control enters, put a +1/+1 counter on each creature you control with lesser power or lesser toughness than that creature.

When Gate of Realms enters, you may search your library for a land card, reveal it, and put that card into your hand. If you do, shuffle.
{10}, {T}: Gate of Realms deals 3 damage to any target. This ability costs {1} less to activate for each different name among lands you control.

Whenever you cast a noncreature spell, put a quest counter on Gate to the Beyond.
At the beginning of your upkeep, if there are three or more quest counters on Gate to the Beyond, you draw a card and you lose 1 life. Then if there are six or more quest counters on it, each opponent loses 2 life.

{T}, Pay 2 life: Add {B}.
{T}: Add one mana of any color. Spend this mana only to cast spells from your graveyard or activate abilities of cards in your graveyard.

You may cast Gateblessed Explorer from your graveyard as long as you control three or more creatures.
Whenever another creature dies, each opponent loses 1 life and you gain 1 life.

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.

Whenever one or more +1/+1 counters are put on a creature you control, you may search your library for a creature card, reveal it, put it into your hand, then shuffle.

At the beginning of your upkeep, mill two cards.
{1}{B}{B}: Until end of turn, Gaunt Abnormality becomes a copy of target creature card in your graveyard, except it's 3/3.

[+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).

Pressure {1}{U}{U} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Draw three cards.

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.

Choose flying, prowess, vigilance, or ward {2}. Create a colorless Equipment artifact token with “Equipped creature has the chosen ability” and equip {2}. (Then exile this card. You may cast the creature later from exile.)

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.”

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.

GenTech Labs enters tapped.
{T}: Add {G} or {U}.
{G}{U}, {T}: Create a Function token with “This spell costs {1} less to cast if its mana value is 5 or greater.” Activate only if you have four or more cards in hand. (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)