Edgeland Market enters tapped unless you control a basic non-Mountain land.
{T}: Add {R}.
{2}{R}, {T}: Create a 0/1 white Goat creature token.

When Electromagnetic Geode enters, draw a card.
{2}, {T}, Sacrifice Electromagnetic Geode: Add two mana of different colors.

Elephant of the Golden Palace enters with your choice of a lifelink counter or an indestructible counter on it if {W} was spent to cast it. The same is true for flying or ward {2} and {U}, deathtouch or menace and {B}, haste or double strike and {R}, and vigilance or trample and {G}.

Exile the top four cards of your library. You may play them until you play a card not exiled this way.

Ephemeral Mire enters tapped.
{T}: Add {U} or {B}.
{4}{U/B}: Until end of turn, Ephemeral Mire becomes a 3/2 black and blue Horror creature until end of turn and can't be blocked this turn. It's still a land. This ability costs {X} less to activate, where X is your devotion to black and blue. Activate only once each turn.

{T}: Add {C}.
{2}, {T}: For each color among permanents you control, add one mana of that color.

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Executive Office enters tapped.
{T}: Add {B} or {R}.
{4}: Make a pledge. Activate only as a sorcery.

{3}, {T}, Sacrifice Explosive Canister: Explosive Canister deals 3 damage to any target.

When Extravagant Patisserie enters, create a Food token.
{T}: Add {C}.

Flash
When Fencer's Foil enters, you may attach it to target creature you control.
Equipped creature gets +2/+0.
Equip {3}

Field Laboratory enters tapped.
{T}: Add {G} or {U}.
{1}, Discard Field Laboratory: Scry 2.

Draw a card. If you control no creatures, create a 1/1 colorless Cyborg artifact creature token.

Flooded Morass enters tapped unless you control a basic Island or a basic Swamp.

Flourishing Crevasse enters tapped unless you control a basic Mountain or a basic Forest.

This spell costs {1} less to cast if it targets a spell you control and costs {1} less to cast if it targets a spell with mana value 3 or less.
Copy target spell. You may choose new targets for the copy.

Flying
{T}: Add {C}.
Spellcharge 4

Equipped creature gets +2/+2 and can't be blocked by more than one creature.
Equip {4}

When Forgemaster Dreadnought enters, create three Treasure tokens.
Spellcharge 9

Whenever Forgotten Cultivator enters or attacks, mill three cards. Return a permanent card from among the milled cards to your hand.
Spellcharge 4

Frostfire Geysers enters tapped unless you control a basic Island or a basic Mountain.

Fungal Mire enters tapped unless you control a basic Swamp or a basic Forest.

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast Shrine spells or activate abilities of Shrines.

Gates to the Underworld enters tapped.
{T}: Add {W} or {B}.
{5}{W/B}: Gates to the Underworld becomes a 3/4 white and black Construct creature with lifelink until end of turn. It's still a land. This ability costs {X} less to activate, where X is your devotion to white and black. Activate only once each turn.