Keyword: Threshold

: Add . Barbarian Ring deals 1 damage to you.
Threshold — , , Sacrifice Barbarian Ring: It deals 2 damage to any target. Activate this ability only if seven or more cards are in your graveyard.

: Add .
Threshold — Werebear gets +3/+3 as long as seven or more cards are in your graveyard.

: Add .
Threshold — : Nantuko Monastery becomes a 4/4 green and white Insect Monk creature with first strike until end of turn. It’s still a land. Activate this ability only if seven or more cards are in your graveyard.

Protection from black
Threshold — As long as seven or more cards are in your graveyard, Mystic Enforcer gets +3/+3 and has flying.

, Discard a card: Regenerate Dirty Wererat.
Threshold — As long as seven or more cards are in your graveyard, Dirty Wererat gets +2/+2 and can’t block.

, Discard a card: Regenerate Dirty Wererat.
Threshold — As long as seven or more cards are in your graveyard, Dirty Wererat gets +2/+2 and can’t block.

Destroy all creatures. They can’t be regenerated.
Threshold — If seven or more cards are in your graveyard, instead destroy all creatures, then create two 1/1 white Spirit creature tokens with flying. Creatures destroyed this way can’t be regenerated.

, Discard a card: Regenerate Dirty Wererat.
Threshold — As long as seven or more cards are in your graveyard, Dirty Wererat gets +2/+2 and can’t block.

, Discard a card: Regenerate Dirty Wererat.
Threshold — As long as seven or more cards are in your graveyard, Dirty Wererat gets +2/+2 and can’t block.

Return target creature card from your graveyard to your hand.
Threshold — Return that card from your graveyard to the battlefield instead if seven or more cards are in your graveyard.

: Add . Centaur Garden deals 1 damage to you.
Threshold — , , Sacrifice Centaur Garden: Target creature gets +3/+3 until end of turn. Activate this ability only if seven or more cards are in your graveyard.

Return target creature card from your graveyard to your hand.
Threshold — Return that card from your graveyard to the battlefield instead if seven or more cards are in your graveyard.

: Add .
Threshold — Werebear gets +3/+3 as long as seven or more cards are in your graveyard.

Shroud (This creature can’t be the target of spells or abilities.)
Threshold — Nimble Mongoose gets +2/+2 as long as seven or more cards are in your graveyard.

Reach (This creature can block creatures with flying.)
Threshold — Seton’s Scout gets +2/+2 as long as seven or more cards are in your graveyard.

: Add . Cephalid Coliseum deals 1 damage to you.
Threshold — , , Sacrifice Cephalid Coliseum: Target player draws three cards, then discards three cards. Activate this ability only if seven or more cards are in your graveyard.

Return target creature card from your graveyard to your hand.
Threshold — Return that card from your graveyard to the battlefield instead if seven or more cards are in your graveyard.

Flying
Threshold — Other creatures you control get +2/+2 as long as seven or more cards are in your graveyard.

Lightning Surge deals 4 damage to any target.
Threshold — If seven or more cards are in your graveyard, instead Lightning Surge deals 6 damage to that permanent or player and the damage can’t be prevented.
Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Flying
Threshold — As long as seven or more cards are in your graveyard, Fledgling Dragon gets +3/+3 and has “: Fledgling Dragon gets +1/+0 until end of turn.”

Flying
Whenever Treacherous Vampire attacks or blocks, sacrifice it unless you exile a card from your graveyard.
Threshold — As long as seven or more cards are in your graveyard, Treacherous Vampire gets +2/+2 and has “When Treacherous Vampire dies, you lose 6 life.”

Target nonblack creature gets -1/-1 until end of turn.
Threshold — If seven or more cards are in your graveyard, instead destroy that creature. It can’t be regenerated.

Threshold — Anurid Barkripper gets +2/+2 as long as seven or more cards are in your graveyard.

Threshold — Put three cards from your graveyard on the bottom of your library: Battlefield Scrounger gets +3/+3 until end of turn. Activate this ability only once each turn and only if seven or more cards are in your graveyard.

Threshold — As long as seven or more cards are in your graveyard, Treacherous Werewolf gets +2/+2 and has “When Treacherous Werewolf dies, you lose 4 life.”