Aeolipile

{1}, {T}, Sacrifice this artifact: It deals 2 damage to any target.

Derelor

Black spells you cast cost {B} more to cast.

Thallid

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.

Elvish Farmer

At the beginning of your upkeep, put a spore counter on this creature.
Remove three spore counters from this creature: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: You gain 2 life.

Soul Exchange

As an additional cost to cast this spell, exile a creature you control.
Return target creature card from your graveyard to the battlefield. Put a +2/+2 counter on that creature if the exiled creature was a Thrull.

Thrull Champion

Thrull creatures get +1/+1.
{T}: Gain control of target Thrull for as long as you control this creature.

Forest

Elvish Hunter

{1}{G}, {T}: Target creature doesn't untap during its controller's next untap step.

Elvish Scout

{G}, {T}: Untap target attacking creature you control. Prevent all combat damage that would be dealt to and dealt by it this turn.

Armor Thrull

{T}, Sacrifice this creature: Put a +1/+2 counter on target creature.

Swamp

Elven Lyre

{1}, {T}, Sacrifice this artifact: Target creature gets +2/+2 until end of turn.

Spore Cloud

Tap all blocking creatures. Prevent all combat damage that would be dealt this turn. Each attacking creature and each blocking creature doesn't untap during its controller's next untap step.

Breeding Pit

At the beginning of your upkeep, sacrifice this enchantment unless you pay {B}{B}.
At the beginning of your end step, create a 0/1 black Thrull creature token.

Thrull Retainer

Enchant creature
Enchanted creature gets +1/+1.
Sacrifice this Aura: Regenerate enchanted creature.