Fledgling Osprey has flying as long as it's enchanted.

Enchant creature

When Flight of Fancy enters, draw two cards.

Enchanted creature has flying.

Whenever Fludge, Gunk Guardian or another Slug, Ooze, Fungus, or Mutant enters the battlefield under your control, each opponent shuffles three Gunk cards into their library. (Gunk is a colorless sorcery card with no mana cost that has cycling .)

Create two 2/3 red Minotaur creature tokens with haste.

Enchant creature

Enchanted creature has flying and "Whenever this creature deals combat damage to a player, venture into the dungeon." (Enter the first room or advance to the next room.)

, : Target creature gains flying until end of turn.

Flying

, Sacrifice Font of Fertility: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Return target creature card from your graveyard to the battlefield. Sacrifice that creature at the beginning of the next end step.

Amass Orcs 2. When you do, Foray of Orcs deals X damage to target creature an opponent controls, where X is the amassed Army's power. (To amass Orcs 2, put two +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

If you would draw a card, return a card from your graveyard to your hand instead. If you can't, you lose the game.

If a card would be put into your graveyard from anywhere, exile that card instead.

Trample

: Add . When you spend this mana to cast an instant or sorcery spell with mana value 3 or less, you may exile that spell instead of putting it into its owner's graveyard as it resolves.

, : You may cast any number of spells from among cards exiled with Forger's Foundry without paying their mana costs. Activate only as a sorcery.

Foriysian Brigade can block an additional creature each combat.

: Add .

: Foriysian Totem becomes a 4/4 red Giant artifact creature with trample until end of turn.

As long as Foriysian Totem is a creature, it can block an additional creature each combat.

Exile target artifact or enchantment.

Cycling (, Discard this card: Draw a card.)

Forsaken Sanctuary enters tapped.

: Add or .

You gain 2 life. Target creature gets +X/+X until end of turn, where X is the amount of life you gained this turn.

Whenever Fortress Cyclops attacks, it gets +3/+0 until end of turn.

Whenever Fortress Cyclops blocks, it gets +0/+3 until end of turn.

When Foul Emissary enters, look at the top four cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

When you sacrifice Foul Emissary while casting a spell with emerge, create a 3/2 colorless Eldrazi Horror creature token.

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for .)

When Foundry Champion enters, it deals damage to any target equal to the number of creatures you control.

: Foundry Champion gets +1/+0 until end of turn.

: Foundry Champion gets +0/+1 until end of turn.

Flying

When Foundry Hornet enters, if you control a creature with a +1/+1 counter on it, creatures your opponents control get -1/-1 until end of turn.

: Add .

, , Sacrifice Foundry of the Consuls: Create two 1/1 colorless Thopter artifact creature tokens with flying.

Whenever another red creature you control enters, Foundry Street Denizen gets +1/+0 until end of turn.

Enchant creature

Enchanted creature loses all abilities and is a Bird creature with base power and toughness 1/1.

Enchant creature

Whenever enchanted creature becomes the target of a spell or ability, that spell or ability's controller gains control of that creature. (This effect lasts indefinitely.)

Exile target nontoken artifact, creature, or enchantment. Its controller puts a random creature card with lesser mana value from their library onto the battlefield tapped.

When Fraying Line enters, put a rope counter on target creature you control.

At the beginning of each player's upkeep, that player may pay . If they do, they put a rope counter on a creature they control. Otherwise, exile Fraying Line and each creature without a rope counter on it, then remove all rope counters from all creatures.

Enchant player

At the beginning of each end step, enchanted player mills X cards, where X is the number of cards put into their graveyard from anywhere this turn.

Riot (This creature enters with your choice of a +1/+1 counter or haste.)

Trample

: Frenzied Arynx gets +3/+0 until end of turn.

Fretwork Colony can't block.

At the beginning of your upkeep, put a +1/+1 counter on Fretwork Colony and you lose 1 life.

+2: Create a 1/1 green Elf Druid creature token with ": Add ."

−2: Destroy target artifact or enchantment.

−6: Draw a card for each green creature you control.

Freyalise, Llanowar's Fury can be your commander.

Whenever an opponent casts a black spell, you may pay . If you do, you draw a card.

: Return Freyalise's Charm to its owner's hand.

Whenever a permanent becomes tapped, put a wind counter on it.

If a permanent with a wind counter on it would untap during its controller's untap step, remove all wind counters from it instead.

Target creature's controller reveals a card at random from their hand. Friendly Fire deals damage to that creature and that player equal to the revealed card's mana value.

Target creature you control and up to one other target legendary creature you control each deal damage equal to their power to target creature you don't control.

Flash

When Frilled Mystic enters, you may counter target spell.

When CARDNAME enters the battlefield, target opponent reveals their hand. Choose a nonland card from it. Ransom that card. (Exile it. Its owner may pay at any time to return it to their hand.)

Devoid (This card has no color.)

At the beginning of your upkeep, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add ."

, Sacrifice From Beyond: Search your library for an Eldrazi card, reveal it, put it into your hand, then shuffle.

When Frost Lynx enters, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

This spell costs less to cast if you control a Giant or a Wizard.

When Frostpyre Arcanist enters, search your library for an instant or sorcery card with the same name as a card in your graveyard, reveal it, put it into your hand, then shuffle.

Target creature gets +3/+3 until end of turn. Put a trample counter on it.

Exile target card from a graveyard. Its owner creates a 1/1 white Spirit creature token with flying.

Double strike

When Fury enters, it deals 4 damage divided as you choose among any number of target creatures and/or planeswalkers.

Evoke—Exile a red card from your hand.

You may exile two red cards from your hand rather than pay this spell's mana cost.

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

When you cast this spell, copy it for each time you've cast your commander from the command zone this game. You may choose new targets for the copies.

Copy target instant or sorcery spell. You may choose new targets for the copy.

Bloodthirst 6 (If an opponent was dealt damage this turn, this creature enters with six +1/+1 counters on it.)

Flying

When Furystoke Giant enters, other creatures you control gain ": This creature deals 2 damage to any target" until end of turn.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Enchant creature

Fylgja enters with four healing counters on it.

Remove a healing counter from Fylgja: Prevent the next 1 damage that would be dealt to enchanted creature this turn.

: Put a healing counter on Fylgja.