msem-instigator

{T}: Add {C}.
{1}, {T}, Sacrifice a creature: Create a 1/1 colorless Spirit creature token.

{T}: Add {C}.
{5}, {T}, Sacrifice Forgotten Monument: Create a tapped 4/4 colorless Golem artifact creature token.

({T}: Add {B}.)
Forgotten Pit enters the battlefield tapped.
Deathtouch
{2}{B}{B}: Forgotten Pit becomes a creature in addition to its other types until end of turn.

{T}, Pay 1 life: Add {R} or {G}.
{1}, {T}, Sacrifice Forgotten Shrine: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

({T}: Add {R} or {W}.)
Whenever Forgotten Steppe becomes tapped, you lose 1 life unless you control two or more basic lands.

{T}: Add {C}. Exile a card from your graveyard.
{3}: Until end of turn, Forgotten Temple becomes an X/X creature, where X is the number of cards exiled by it. It's still a land.
As long as a creature card with flying is exiled by Forgotten Temple, it has flying. The same is true for first strike, double strike, deathtouch, experience, haste, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance.

({T}: Add {U} or {B}.)
As Forlorn Ruin enters the battlefield, you may pay {1}. If you don't, Forlorn Ruin enters the battlefield tapped.

{T}: Add {C}.
{T}, Reappropriate: Add {W} or {B}. (Exile exactly two cards from your hand and/or graveyard.)

{T}: Add {B} or {G}. You lose 1 life unless you have less life than an opponent.

As Fortified Village enters the battlefield, you may reveal a Forest or Plains card from your hand. If you don't, Fortified Village enters the battlefield tapped.
{T}: Add {G} or {W}.

Fortress Arena enters the battlefield tapped.
{T}: Add {R} or {W}.
{2}{R}{W}, {T}, Sacrifice Fortress Arena: Draw a card.

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only during an opponent's turn.

Frigid Highlands enters the battlefield tapped unless you control an Island.
{T}: Add {R} or {G}.

{T}: Add {C}.
{T}, Pay 1 life: Add {G} or {W}.

Frondpond Grotto enters the battlefield tapped unless you played it from exile.
{T}: Add {U} or {B}.

Frontier Base enters the battlefield tapped unless you have 15 or less life.
{T}: Add {G} or {U}.

({T}: Add {U} or {R}.)
Frostfire Geysers enters the battlefield tapped unless you control a basic Island or a basic Mountain.

Frostpoint Caldera enters the battlefield tapped unless you control a basic land.
{T}: Add {U} or {R}.

Frozen Hinterlands enters the battlefield tapped.
{T}: Add {W} or {U}.
{1}{W}{U}: Until end of turn, Frozen Hinterlands becomes a 4/3 white and blue Spirit creature with with prowess and “Whenever this creature attacks or blocks, torment yourself.” It's still a land. (To torment yourself, lose 3 life unless you discard a card or sacrifice a nonland permanent.)

[+2]: Draw two cards, then discard two cards unless you discard an instant or sorcery card.
[–3]: Reveal any number of cards from your hand. Fulmen deals damage to any target equal to the number of instant and sorcery cards revealed.
[–9]: Search each player's library for up to one instant card and one sorcery card. Cast those cards without paying their mana costs. Then each player shuffles.

({T}: Add {B} or {G}.)
Fungal Mire enters the battlefield tapped unless you control a basic Swamp or a basic Forest.

Flying, vigilance
At the beginning of your upkeep, if you have 10 or more life than your starting life total, put a +1/+1 counter on each other creature you control.

As Game Trail enters the battlefield, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters the battlefield tapped.
{T}: Add {R} or {G}.

(Transform this if it's not attached to a creature. Pay {R} as a sorcery to unattach it.)
Enchant creature you control
Gamhaugen War Swine's rider gets +1/+1 and has haste.

(Transform this if it's not attached to a creature. Pay {3}{U} as a sorcery to unattach it.)
Enchant creature you control
Gamhaugen Warbeast's rider gets +2/+2 and has flying.