When Fang of Andazir enters, each player sacrifices a permanent. Whenever you sacrifice a creature for the first time each turn, create a 1/1 red Dog creature token.
Whenever Fangs of Wesgoth deals combat damage to a player, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.) As long as you control three or more artifacts, Fangs of Wesgoth has menace.
She exacts vengeance on those that turned her against her will.
Flying {1}{U}, Sacrifice Fatewrench: Fateseal 2. (To fateseal 2, look at the top two cards of an opponent's library, then put any number of them on the bottom of that player's library and the rest on top in any order.)
No secret is safe from Mei's students, not even those that haven't been thought of yet.
Haste Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) When Favoured Firebrand dies, you may pay {U}{R} any number of times. Whenever you do, Favoured Firebrand deals 2 damage to any target and you draw a card.
Haste Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
“Why fear death? Ifram has promised that it won't be stagnation.”
When Fearless King Shabil enters, reveal the top five cards of your library. You may put a Cat card from among them into your hand. Put the rest on the bottom of your library in any order. At the beginning of combat on your turn, each Cat you control gains all abilities of each other Cat you control until end of turn.
When Fearless Realmwalker enters, put a +1/+1 counter on each of up to two target creatures. Whenever Fearless Realmwalker attacks, you may pay {2}{W}. If you do, aetherize it. (To aetherize, create a token that's a copy of it, then exile that token.)
When Fellor Ironborn enters, you may return target artifact card from your graveyard to the battlefield. If it's an Equipment, you may attach it to target creature you control.
Harmony — Target creature you control gets +1/+0 and gains first strike until end of turn. When Fellor War-Skald enters, harmonize. (Trigger up to one harmony of a permanent you control.)
Menace When Fenhauler Gang enters, each player mills three cards. Whenever Fenhauler Gang deals combat damage to a player, return up to one target creature or land card from your graveyard to your hand.
{R/G}: Fento, Nova Crusader gains haste and trample until end of turn. Whenever Fento, Nova Crusader attacks, you may put a creature card from your hand onto the battlefield tapped and attacking. If you do, sacrifice that creature at the beginning of the next end step.
Trample When Feral Devout enters, choose one — • Put a +1/+1 counter on Feral Devout. • Create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”
When Ferocity of the Redeemed enters, return up to two target creature cards with mana value 1 or less from your graveyard to the battlefield. Revive {2}{W}{W}({2}{W}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)