msem-instigator

When Gilded Merrow enters, if an opponent controls more lands than you, create a Treasure token. (It's an artifact with “{T}, Sacrifice this permanent: Add one mana of any color.”)

Menace
Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Gilded Sell-Sword gets +2/+0 as long as you're in a renaissance.

Flying
Whenever a player shuffles their library, Gilded Wyvern deals 2 damage to that player.

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.

Harmony — Target creature gains flying until end of turn.
When Glamorous Aerialist enters, harmonize. (Trigger up to one harmony of one permanent you control.)

Flying

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 Gleaming Rider envisions an instant or sorcery card, target creature becomes a 5/5 Elk Spirit until end of turn.

When Gleeful Deviser enters, create a 1/1 colorless Construct artifact creature token.

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

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Instant and sorcery spells you control have wither. (They deal damage to creatures in the form of -1/-1 counters.)

Prismatic — Whenever you cast a multicolored spell, draw a card.

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.

Gloaming Smokeweaver has deathtouch as long as there is a creature card in your graveyard.

Flying
Whenever you cast a noncreature spell, create a 1/1 blue Faerie Rogue creature token with flying.
Whenever one or more creature tokens you control deal combat damage to a player, you may pay {G/U}. If you do, draw a card.

Attacking creatures you control have first strike.
Whenever three or more creatures you control die, Glorysinger deals 4 damage to any target.

When Glymna Blackrune enters, exile target player's graveyard.
During each of your turns, you may cast a creature card exiled with Glymna Blackrune.

Whenever you cast an instant or sorcery spell, create a Treasure Clue token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color” and “{2}, Sacrifice this artifact: Draw a card.)

When Gnuge-District Hoarder enters, each opponent loses 1 life. You gain life equal to the life lost this way.
Paranoia {1}{B} (You may cast this spell for its paranoia cost when a permanent you control leaves the battlefield.)

When Goblin Cutpurses enters, target player discards a card, then draws a card.

Prowess
{3}{R}, Sacrifice Goblin Experimenter: Return target sorcery card from your graveyard to your hand.

Whenever Goblin Raidleader attacks, create a 1/1 red Goblin creature token that's tapped and attacking.
{1}{R}: Other Goblins you control get +1/+0 until end of turn.

Whenever you cast an instant or sorcery spell, target creature can't block this turn.

Whenever you cast a spell you don't own, you may pay {1}{U}. If you do, put target nonland permanent on top of its owner's library.
{2}{B}: Exile the top card of target opponent's library face down. You may look at and cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any type to cast that spell.

When Godseeker Vanguard enters, create two 1/1 green Scout creature tokens.