Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Merciless Executioner

When Merciless Executioner enters the battlefield, each player sacrifices a creature.

Dawntreader Elk

{G}, Sacrifice Dawntreader Elk: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Forest

Demon's Disciple

When Demon's Disciple enters the battlefield, each player sacrifices a creature or planeswalker.

Plaguecrafter

When Plaguecrafter enters the battlefield, each player sacrifices a creature or planeswalker. Each player who can't discards a card.

Jadar, Ghoulcaller of Nephalia

At the beginning of your end step, if you control no creatures with decayed, create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Veinwitch Coven

Menace
Whenever you gain life, you may pay {B}. If you do, return target creature card from your graveyard to your hand.

Swamp

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Diligent Farmhand

{1}{G}, Sacrifice Diligent Farmhand: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
If Diligent Farmhand is in a graveyard, effects from spells named Muscle Burst count it as a card named Muscle Burst.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Phyrexian Reclamation

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

Cankerbloom

{1}, Sacrifice Cankerbloom: Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Neverwinter Dryad

{2}, Sacrifice Neverwinter Dryad: Search your library for a basic Forest card, put it onto the battlefield tapped, then shuffle.

Savra, Queen of the Golgari

Whenever you sacrifice a black creature, you may pay 2 life. If you do, each other player sacrifices a creature.
Whenever you sacrifice a green creature, you may gain 2 life.

Fleshbag Marauder

When Fleshbag Marauder enters the battlefield, each player sacrifices a creature.