msem-instigator

Equipped creature gets +1/+1.
Sacrifice Forceglow Shield: Prevent all damage a source of your choice would deal to equipped creature this turn.
Equip {2}

When Forebear of Hibernation enters, each player may search their library for a creature card, reveal it, put it into their hand, then shuffle. Then you choose a nonland card name.
Spells with the chosen name cost {2} more to cast.

If a spell, ability, or creature an opponent controls would deal 4 or more damage to you or cause you to lose 4 or more life, you lose 4 life instead. (Damage won't be dealt.)

At the beginning of each combat, prevent all combat damage that would be dealt to and dealt by up to one target creature this turn.
{X}{G}{U}, Sacrifice Foreboding Calm: Create an X/X green and blue Plant Horror creature token with hexproof and trample.

Whenever a player casts a spell, put a doom counter on Foreboding Presence.
At the beginning of each player's end step, if no spells were cast this turn, sacrifice Foreboding Presence. It deals damage equal to the number of doom counters on it to that player.

As Foreboding Ruins enters, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters tapped.
{T}: Add {B} or {R}.

{2}, Exile a card with a cycling ability from your graveyard: Draw a card.
Cycling {3}{G} ({3}{G}, Discard this card: Draw a card.)
When you cycle Foregone Ancestries, you may exile it. If you do, return target card with a cycling ability from your graveyard to your hand.

Enchant player
At the beginning of enchanted player's upkeep, up to two target creatures they control gain winnow until end of turn. (Damage dealt to a creature with winnow also causes its controller to lose that much life.)

When Forerunner of the Briar enters, sacrifice two lands. When you do, choose one —
• Create a 3/3 green Beast creature token.
• Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Mimic {2} ({2}: This takes the shape of your choice. Mimic only as a sorcery.) [3/3]
[shape 1] Flying, double strike [3/3]
[shape 2] Hexproof
{T}: Put two +1/+1 counters on Forest Dragon Telo. [3/3]

When Forest Whale dies, put a number of +1/+1 counters on target creature you control equal to Forest Whale's power.

Hexproof

Forestheart Elemental enters with a +1/+1 counter on it for each land you control.

Heroic — Whenever you cast a spell that targets Forge Adept, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)
{6}{R}: Create a 3/3 colorless Golem enchantment artifact creature token. If mana from an artifact was spent to activate this ability, that token gains haste.

Attacking creatures you control have “{R}: This creature gets +1/+0 until end of turn.”
Armed — Whenever Forgeborn Barbarian attacks, add {R} for each equipped creature you control.

Whenever you cast an artifact spell, create a 1/1 colorless Construct artifact creature token.

{T}, Sacrifice Forgewatcher: Add two mana of any one color. If that mana is spent on a creature spell, it gains haste until end of turn.

Equipped creature has first strike.
{R}: Equipped creature gets +1/+0 until end of turn.
Equip {2}

{1}: Exile target card from a graveyard. That card's owner may scry 1.

Forgotten Attic enters tapped.
When Forgotten Attic enters, look at the top card of your library. You may put it into your graveyard.
{T}: Add {U} or {B}.

Forgotten Cryovault enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast spells from your graveyard.

Forgotten Experiment can't be blocked.

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