Infiltration Lens

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

Cunning Evasion

Whenever a creature you control becomes blocked, you may return it to its owner's hand.

Somberwald Vigilante

Whenever Somberwald Vigilante becomes blocked by a creature, Somberwald Vigilante deals 1 damage to that creature.

Elvish Berserker

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

Tangle Asp

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

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter with your choice of a +1/+1 counter or haste.)

Dead-Iron Sledge

Whenever equipped creature blocks or becomes blocked by a creature, destroy both creatures.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Averna, the Chaos Bloom

As you cascade, you may put a land card from among the exiled cards onto the battlefield tapped. (Do this after the last card is exiled but before deciding whether to cast a nonland card.)

Grazilaxx, Illithid Scholar

Whenever a creature you control becomes blocked, you may return it to its owner's hand.
Whenever one or more creatures you control deal combat damage to a player, draw a card.

Violent Outburst

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Creatures you control get +1/+0 until end of turn.