msem-instigator

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.

Flying, prowess
{T}: Until end of turn, target land is every basic land type in addition to its other types.

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

When Glamorous Festivities enters or at the beginning of your upkeep, you may put two +1/+1 counters on each creature you control. If you do, each opponent may put a +1/+1 counter on each creature they control.

{2}{W}, Sacrifice Gleamhorn Elk: Destroy target artifact or enchantment.

When Gleamhorn Gargantuan enters, put a +1/+1 counter on up to one other target creature.
Cycling {2} ({2}, Discard this card: Draw a card.)

Flying

Whenever you draw your second card each turn, other creatures you control get +1/+1 and gain indestructible until end of turn.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Gleaming Hot Springs enters tapped unless you control a Mountain.
{T}: Add {W} or {U}.

Flying
Whenever an opponent casts a spell, copy it. You may choose new targets for the copy.

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.

{T}, Pay 1 life: Add {U}.
{T}, Pay 1 life, Sacrifice Gleaming River: Search your library for an Island card, put it onto the battlefield tapped, then shuffle.

Gleaming Veldt enters tapped unless another player controls a land that could produce {G} or {W}.
{T}: Add {G} or {W}.

When Gleaming Waypoint enters, create a 1/1 red Scout creature token.
{T}: Add {U}, {R}, or {W}.

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.)

Aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)
Draw a card.

Prowess
Wither (This deals damage to creatures in the form of -1/-1 counters.)

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.

Trial 3 (As you cast this spell, an opponent of your choice may pay 3 life. If they don't, they fail the trial.)
When Glimmering Prosecutor enters, if the trial was failed, create two 1/1 black Devil creature tokens.

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.)

{3}, {T}: Glimmering Staff deals 1 damage to any target.
{5}, {T}: Put a -1/-1 counter on target creature.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever Glimmerwing Trickster deals combat damage to a player, scry 2.