msem-instigator

Garden Cherub's power and toughness are each equal to the number of creatures you control.
Garden Cherub can't be blocked by creatures with power 2 or less.

{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.

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.

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.)

{T}: Add {C}.
{T}: Choose a color from among permanents you control. Add one mana of that color.

Generative Edge enters tapped.
{T}: Add {G} or {U}.
{G}{U}, {T}, Sacrifice Generative Edge: Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Ghastly Castle enters tapped unless another player controls a land that could produce {U} or {B}.
{T}: Add {U} or {B}.

Creatures can't attack you or a planeswalker you control unless their controller pays {2} for each of those creatures.
Creatures can't block Ghastly Scraper unless their controller pays {2} for each of those creatures.

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

({T}: Add {U} or {B}.)
Ghostspore Mire enters tapped.
{1}, {T}: Add {U}{U} or {B}{B}.

{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.

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.)

{T}: Add {C}.
{T}, Sacrifice Gilded Gulch: Add one mana of any color.
When you discard Gilded Gulch, you may pay {1}. If you do, create a tapped colorless land token named Fading Rift with “{T}, Sacrifice this land: Add one mana of any color.”

You may choose not to untap Glacial Shelf during your untap step.
{T}: Add {C}.
{4}, {T}: Tap target creature that's attacking you. It doesn't untap during its controller's untap step for as long as Glacial Shelf remains tapped.

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

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

{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}.

({T}: Add {R} or {G}.)
Glittering Grove enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {W} or {B}.)
Gloomcover Steppe enters tapped unless you control a basic Plains or a basic Swamp.

Gloomhollow Woodlock enters tapped unless you played it from exile.
{T}: Add {B} or {G}.

Gloomtide Gulf enters tapped.
{T}: Add {U} or {B}.
{1}, {T}: Add one mana of any color.

Enchant creature
Enchanted creature has “You can't lose the game and your opponents can't win the game.”

({T}: Add {R} or {W}.)
Gnarled Henge enters tapped unless you control two or more basic lands.

Golden Glade enters tapped.
{1}, {T}: Add two mana of any one color.