Plains

Gatebreaker Ram

Gatebreaker Ram gets +1/+1 for each Gate you control.
As long as you control two or more Gates, Gatebreaker Ram has vigilance and trample.

Plaza of Harmony

When Plaza of Harmony enters, if you control two or more Gates, you gain 3 life.
{T}: Add {C}.
{T}: Add one mana of any type that a Gate you control could produce.

Mountain

Guild Summit

When Guild Summit enters, you may tap any number of untapped Gates you control. Draw a card for each Gate tapped this way.
Whenever a Gate you control enters, draw a card.

Crackling Perimeter

Tap an untapped Gate you control: Crackling Perimeter deals 1 damage to each opponent.

Gatekeeper Gargoyle

Flying
Gatekeeper Gargoyle enters with a +1/+1 counter on it for each Gate you control.

Gates Ablaze

Gates Ablaze deals X damage to each creature, where X is the number of Gates you control.

Island

Hold the Gates

Creatures you control get +0/+1 for each Gate you control and have vigilance.

Gruul Guildgate

This land enters tapped.
{T}: Add {R} or {G}.

Gate Colossus

This spell costs {1} less to cast for each Gate you control.
This creature can't be blocked by creatures with power 2 or less.
Whenever a Gate you control enters, you may put this card from your graveyard on top of your library.

Simic Guildgate

This land enters tapped.
{T}: Add {G} or {U}.

Glaive of the Guildpact

Equipped creature gets +1/+0 for each Gate you control and has vigilance and menace. (A creature with menace can't be blocked except by two or more creatures.)
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Maze's End

This land enters tapped.
{T}: Add {C}.
{3}, {T}, Return this land to its owner's hand: Search your library for a Gate card, put it onto the battlefield, then shuffle. If you control ten or more Gates with different names, you win the game.

Boros Guildgate

This land enters tapped.
{T}: Add {R} or {W}.

Gateway Plaza

Gateway Plaza enters tapped.
When Gateway Plaza enters, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Forest

Saruli Gatekeepers

When Saruli Gatekeepers enters, if you control two or more Gates, you gain 7 life.