Bloodcrazed Goblin can't attack unless an opponent has been dealt damage this turn.

Target creature gets +X/+0 until end of turn.

Whenever you draw your second card each turn, Bloodhaze Wolverine gets +1/+1 and gains first strike until end of turn.

Flying

: Create a 2/2 black Vampire creature token with flying.

: Transform Bloodline Keeper. Activate only if you control five or more Vampires.

Changeling (This card is every creature type.)

As Bloodline Pretender enters, choose a creature type.

Whenever another creature you control of the chosen type enters, put a +1/+1 counter on Bloodline Pretender.

: Target creature gains haste until end of turn. (It can attack and this turn.)

: Target player loses 3 life and you gain 3 life.

This spell costs less to cast for each 1 life your opponents have lost this turn.

Target opponent exiles the top three cards of their library. Until the end of your next turn, you may play those cards. If you cast a spell this way, mana of any type can be spent to cast it.

, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Gift a Treasure (You may promise an opponent a gift as you cast this spell. If you do, they create a Treasure token before its other effects. It's an artifact with ", Sacrifice this artifact: Add one mana of any color.")

Blooming Blast deals 2 damage to target creature. If the gift was promised, Blooming Blast also deals 3 damage to that creature's controller.

Whenever Blossoming Bogbeast attacks, you gain 2 life. Then creatures you control gain trample and get +X/+X until end of turn, where X is the amount of life you gained this turn.

Target creature you control gets +2/+2 and gains hexproof until end of turn.

Whenever Blossoming Tortoise enters or attacks, mill three cards, then return a land card from your graveyard to the battlefield tapped.

Activated abilities of lands you control cost less to activate.

Land creatures you control get +1/+1.

Blow Off Steam deals 1 damage to any target. (Then exile this card. You may cast the creature later from exile.)

Creatures attacking you get -1/-0.

At the beginning of each end step, if you were dealt 4 or more damage this turn, exile Boarded Window.

: Add .

Target creature attacks this turn if able.

Draw a card.

Destroy all Islands.

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)

Whenever this creature attacks, tap target artifact or creature an opponent controls.

Flying

Whenever another creature you control enters, target creature gets +2/+0 until end of turn.

Look at the top three cards of your library. You may reveal a permanent card from among them and put it into your hand. Put the rest on the bottom of your library in any order. You gain 3 life.

Create a tapped 4/1 black Skeleton creature token with menace. (Then exile this card. You may cast the artifact later from exile.)

, Exile Bonebind Orator from your graveyard: Return another target creature card from your graveyard to your hand.

Any player may have Book Burning deal 6 damage to them. If no one does, target player mills six cards.

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following abilities until end of turn.)

Flying, first strike, lifelink

Flying

: Boreal Griffin gains first strike until end of turn. ( can be paid with one mana from a snow source.)

Battalion — Whenever Boros Strike-Captain and at least two other creatures attack, exile the top card of your library. During any turn you attacked with three or more creatures, you may play that card.

Borrowing the East Wind deals X damage to each creature with horsemanship and each player.

Sacrifice a creature. Return up to X cards from your graveyard to your hand, where X is the number of colors that creature was. Exile this card.

Enchant creature

Enchanted creature can't attack or block.

Flash (You may cast this spell any time you could cast an instant.)

When Bounding Krasis enters, you may tap or untap target creature.

Flying

Whenever you cast a Spirit or Arcane spell, you may gain life equal to that spell's mana value.

Roll a six-sided die. Create a number of 1/1 red Goblin creature tokens equal to the result.

Flying

Whenever Brago, King Eternal deals combat damage to a player, exile any number of target nonland permanents you control, then return those cards to the battlefield under their owner's control.

Target player mills three cards.

Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

, : Put a charge counter on Brain in a Jar, then you may cast an instant or sorcery spell with mana value equal to the number of charge counters on Brain in a Jar from your hand without paying its mana cost.

, , Remove X charge counters from Brain in a Jar: Scry X.

Choose a nonland card name. Target player reveals their hand. That player discards a card with that name. If they can't, you draw a card.

Target opponent reveals their hand. You choose a card from it. That player discards that card.

Draw a card.

Destroy target creature that isn't enchanted. It can't be regenerated.

Transmute (, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

, , Sacrifice Brainstone: Draw three cards, then put two cards from your hand on top of your library in any order.

Draw four cards, then put two cards from your hand on top of your library in any order.

Partner with Shabraz, the Skyshark (When this creature enters, target player may put Shabraz into their hand from their library, then shuffle.)

Whenever you discard a card, put a +1/+1 counter on Brallin, Skyshark Rider and it deals 1 damage to each opponent.

: Target Shark gains trample until end of turn.

At the beginning of combat on your turn, target creature you control gets +X/+0 until end of turn, where X is Brambleguard Captain's power.

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

When Brass's Tunnel-Grinder enters, discard any number of cards, then draw that many cards plus one.

At the beginning of your end step, if you descended this turn, put a bore counter on Brass's Tunnel-Grinder. Then if there are three or more bore counters on it, remove those counters and transform it. (You descended if a permanent card was put into your graveyard from anywhere.)

Flash (You may cast this spell any time you could cast an instant.)

When Breaching Hippocamp enters, untap another target creature you control.

: Target creature with power 2 or less gains haste until end of turn and can't be blocked this turn.

Target creature an opponent controls deals damage equal to its power to another target creature that player controls. The Ring tempts you.

You may cast Breaking Wave as though it had flash if you pay more to cast it. (You may cast it any time you could cast an instant.)

Simultaneously untap all tapped creatures and tap all untapped creatures.

(: Add or .)

As Breeding Pool enters, you may pay 2 life. If you don't, it enters tapped.