msem-instigator

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Ghostly Hounds mentors a creature, that creature can't be blocked this turn.

When Ghoulsaber enters, create a 1/1 white Spirit creature token with flying, then attach Ghoulsaber to it.
Equipped creature gets +2/+2.
Equip {2}

{2}, Sacrifice Giant's Remains: Draw a card.
{5}, Exile Giant's Remains from your graveyard: Create a tapped 4/4 black Skeleton Giant artifact creature token.

Sacrifice a creature. At the beginning of the next end step, return that card from a graveyard to the battlefield under your control with two +1/+1 counters on it, except it's a black Demon instead of its other colors and types.

Gifted Arcanomancer gets +1/+1 as long as you control a Mountain.
{3}{R}: Exile the top card of your library. Until end of turn, you may play that card.

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.

When Giku Weaponsmith enters, create two colorless Equipment artifact tokens with “Equipped creature gets +1/+1” and equip {1}.

Gild-Cloak Strider can't be blocked by creatures with greater power.
{1}{W/U}: Return Gild-Cloak Strider to its owner's hand.

When Gilded Authority enters, create two Treasure tokens. (They're artifacts with “{T}, Sacrifice this artifact: Add one mana of any color.”)
Creatures your opponents control get -1/-0.

Renown 2 (When this creature deals combat damage to a player, if it isn't renowned, put two +1/+1 counters on it and it becomes renowned.)
When Gilded Champion becomes renowned, you may search your library for an Equipment or Aura card, reveal it, put it into your hand, then shuffle.

As you harmonize, you may choose another harmony ability to trigger. (They can't be the same harmony.)
Harmony — Scry 1.

Flying
When Gilded Guardian dies, you may search your library for a legendary card, reveal it, put it into your hand, then shuffle.

Trample
{3}, Discard Gilded Ram: Draw a card, gain 2 life, and create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

{T}, Discard a card: Draw a card.
Unveil {2}{U}{R} ({2}{U}{R}: Transform this. Unveil only as a sorcery.)

Trample
Spells your opponents cast that target creatures you control cost {2} more to cast.
Whenever a creature you control attacks alone, it gets +2/+2 until end of turn.

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
Untap each Horror you control during enchanted creature's controller's untap step.

Destroy target creature or planeswalker if damage has been dealt to it this turn. Then Give to Sacred Halls deals 1 damage to it.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Flash
When Giver of Martoob enters, put a +1/+1 counter on each of up to two target creatures you control.

Glacial Vista enters tapped.
{T}: Add {W} or {U}.
{1}, {T}: Add one mana of any color.

{G}{U}: Glacier Tortoise gets +5/-5 until end of turn. Activate only once each turn.

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.

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

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