Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Mindcrank

Whenever an opponent loses life, that player mills that many cards. (Damage causes loss of life.)

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Stinkweed Imp

Flying
Whenever this creature deals combat damage to a creature, destroy that creature.
Dredge 5 (If you would draw a card, you may mill five cards instead. If you do, return this card from your graveyard to your hand.)

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Stitcher's Supplier

When this creature enters or dies, mill three cards. (Put the top three cards of your library into your graveyard.)

Forever Young

Put any number of target creature cards from your graveyard on top of your library.
Draw a card.

Bloodchief Ascension

At the beginning of each end step, if an opponent lost 2 or more life this turn, you may put a quest counter on this enchantment. (Damage causes loss of life.)
Whenever a card is put into an opponent's graveyard from anywhere, if this enchantment has three or more quest counters on it, you may have that player lose 2 life. If you do, you gain 2 life.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.