Hissing Iguanar

Whenever another creature dies, you may have Hissing Iguanar deal 1 damage to target player or planeswalker.

Thromok the Insatiable

Devour X, where X is the number of creatures devoured this way (As this enters, you may sacrifice any number of creatures. This creature enters with X +1/+1 counters on it for each of those creatures.)

Preyseizer Dragon

Flying
Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
Whenever Preyseizer Dragon attacks, it deals damage to any target equal to the number of +1/+1 counters on Preyseizer Dragon.

Hellkite Hatchling

Devour 1 (As this enters, you may sacrifice any number of creatures. This creature enters with that many +1/+1 counters on it.)
Hellkite Hatchling has flying and trample if it devoured a creature.

Mycoloth

Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Thunder-Thrash Elder

Devour 3 (As this enters, you may sacrifice any number of creatures. This creature enters with three times that many +1/+1 counters on it.)

Nullmage Advocate

{T}: Return two target cards from an opponent's graveyard to their hand. Destroy target artifact or enchantment.

Beetleback Chief

When Beetleback Chief enters, create two 1/1 red Goblin creature tokens.

Khalni Garden

Khalni Garden enters tapped.
When Khalni Garden enters, create a 0/1 green Plant creature token.
{T}: Add {G}.

Fires of Yavimaya

Creatures you control have haste.
Sacrifice Fires of Yavimaya: Target creature gets +2/+2 until end of turn.

Penumbra Spider

Reach
When Penumbra Spider dies, create a 2/4 black Spider creature token with reach.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Brindle Shoat

When Brindle Shoat dies, create a 3/3 green Boar creature token.

Gruul Turf

Gruul Turf enters tapped.
When Gruul Turf enters, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Skarrg, the Rage Pits

{T}: Add {C}.
{R}{G}, {T}: Target creature gets +1/+1 and gains trample until end of turn.

Tukatongue Thallid

When Tukatongue Thallid dies, create a 1/1 green Saproling creature token.

Fiery Conclusion

As an additional cost to cast this spell, sacrifice a creature.
Fiery Conclusion deals 5 damage to target creature.

Mark of Mutiny

Gain control of target creature until end of turn. Put a +1/+1 counter on it and untap it. That creature gains haste until end of turn. (It can attack and {T} this turn.)

Forest

Awakening Zone

At the beginning of your upkeep, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Hellion Eruption

Sacrifice all creatures you control, then create that many 4/4 red Hellion creature tokens.

Mountain

Gluttonous Slime

Flash
Devour 1 (As this enters, you may sacrifice any number of creatures. This creature enters with that many +1/+1 counters on it.)

Kazandu Refuge

Kazandu Refuge enters tapped.
When Kazandu Refuge enters, you gain 1 life.
{T}: Add {R} or {G}.

Flayer Husk

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1.
Equip {2}

Mitotic Slime

When Mitotic Slime dies, create two 2/2 green Ooze creature tokens. They have "When this creature dies, create two 1/1 green Ooze creature tokens."

Nest Invader

When Nest Invader enters, create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Dragonlair Spider

Reach
Whenever an opponent casts a spell, create a 1/1 green Insect creature token.

Wall of Blossoms

Defender
When Wall of Blossoms enters, draw a card.

Thorn-Thrash Viashino

Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
{G}: Thorn-Thrash Viashino gains trample until end of turn.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Viridian Emissary

When Viridian Emissary dies, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Mudbutton Torchrunner

When Mudbutton Torchrunner dies, it deals 3 damage to any target.

Overrun

Creatures you control get +3/+3 and gain trample until end of turn. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)