Alley Grifters

Whenever this creature becomes blocked, defending player discards a card.

Taunting Challenge

All creatures able to block target creature this turn do so.

Sparring Golem

Whenever this creature becomes blocked, it gets +1/+1 until end of turn for each creature blocking it.

Alluring Scent

Deepwood Wolverine

Whenever this creature becomes blocked, it gets +2/+0 until end of turn.

Revenge of the Hunted

Until end of turn, target creature gets +6/+6 and gains trample, and all creatures able to block it this turn do so.
Miracle {G} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Corrupt Official

{2}{B}: Regenerate this creature.
Whenever this creature becomes blocked, defending player discards a card at random.

Escaped Null

Lifelink
Whenever this creature blocks or becomes blocked, it gets +5/+0 until end of turn.

Tangle Asp

Whenever this creature blocks or becomes blocked by a creature, destroy that creature at end of combat.

Engulfing Slagwurm

Whenever this creature blocks or becomes blocked by a creature, destroy that creature. You gain life equal to that creature's toughness.

Retaliation

Creatures you control have "Whenever this creature becomes blocked by a creature, this creature gets +1/+1 until end of turn."

Reap

Return up to X target cards from your graveyard to your hand, where X is the number of black permanents target opponent controls as you cast this spell.

Chub Toad

Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.

Cockatrice

Flying
Whenever this creature blocks or becomes blocked by a non-Wall creature, destroy that creature at end of combat.

Slate Street Ruffian

Snorting Gahr

Whenever this creature becomes blocked, it gets +2/+2 until end of turn.

Pharika, God of Affliction

Indestructible
As long as your devotion to black and green is less than seven, Pharika isn't a creature.
{B}{G}: Exile target creature card from a graveyard. Its owner creates a 1/1 black and green Snake enchantment creature token with deathtouch.

Seton's Desire

Enchant creature
Enchanted creature gets +2/+2.
Threshold — As long as seven or more cards are in your graveyard, all creatures able to block enchanted creature do so.

Razorclaw Bear

Sylvan Basilisk

Whenever this creature becomes blocked by a creature, destroy that creature.

Bloodscent

Rabid Elephant

Whenever this creature becomes blocked, it gets +2/+2 until end of turn for each creature blocking it.

Nemesis Mask

All creatures able to block equipped creature do so.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Slashing Tiger

Gorgon Recluse

Whenever this creature blocks or becomes blocked by a nonblack creature, destroy that creature at end of combat.
Madness {B}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Pygmy Kavu

When this creature enters, draw a card for each black creature your opponents control.

Ichorclaw Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this creature becomes blocked, it gets +2/+2 until end of turn.

Wolverine Pack

Rampage 2 (Whenever this creature becomes blocked, it gets +2/+2 until end of turn for each creature blocking it beyond the first.)

Basalt Golem

This creature can't be blocked by artifact creatures.
Whenever this creature becomes blocked by a creature, that creature's controller sacrifices it at end of combat. If the player does, they create a 0/2 colorless Wall artifact creature token with defender.

Venomous Dragonfly

Flying
Whenever this creature blocks or becomes blocked by a creature, destroy that creature at end of combat.

Benefactor's Draught

Untap all creatures. Until end of turn, whenever a creature an opponent controls blocks, draw a card.
Draw a card.

Oversold Cemetery

At the beginning of your upkeep, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Bereavement

Whenever a green creature dies, its controller discards a card.

Tempting Licid

{G}, {T}: This creature loses this ability and becomes an Aura enchantment with enchant creature. Attach it to target creature. You may pay {G} to end this effect.
All creatures able to block enchanted creature do so.

Teeka's Dragon

Flying; trample; rampage 4 (Whenever this creature becomes blocked, it gets +4/+4 until end of turn for each creature blocking it beyond the first.)

Infiltration Lens

Whenever equipped creature becomes blocked by a creature, you may draw two cards.
Equip {1}

Gang of Elk

Shinen of Life's Roar

All creatures able to block this creature do so.
Channel — {2}{G}{G}, Discard this card: All creatures able to block target creature this turn do so.

Noble Quarry

Bestow {5}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
All creatures able to block this creature or enchanted creature do so.
Enchanted creature gets +1/+1.

Zombie Boa

{1}{B}: Choose a color. Whenever this creature becomes blocked by a creature of that color this turn, destroy that creature. Activate only as a sorcery.

Rust Scarab

Whenever this creature becomes blocked, you may destroy target artifact or enchantment defending player controls.

Gorilla Berserkers

Trample; rampage 2 (Whenever this creature becomes blocked, it gets +2/+2 until end of turn for each creature blocking it beyond the first.)
This creature can't be blocked except by three or more creatures.

Thicket Basilisk

Whenever this creature blocks or becomes blocked by a non-Wall creature, destroy that creature at end of combat.

Infernal Medusa

Whenever this creature blocks a creature, destroy that creature at end of combat.
Whenever this creature becomes blocked by a non-Wall creature, destroy that creature at end of combat.

Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap this land for mana, target opponent creates a 1/1 colorless Spirit creature token.

Evil Eye of Urborg

Non-Eye creatures you control can't attack.
Whenever this creature becomes blocked by a creature, destroy that creature.