Spore Crawler

Incubation Druid

{T}: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead.
{3}{G}{G}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)

Dragon Mantle

Enchant creature
When Dragon Mantle enters, draw a card.
Enchanted creature has "{R}: This creature gets +1/+0 until end of turn."

Rubblebelt Rioters

Haste
Whenever Rubblebelt Rioters attacks, it gets +X/+0 until end of turn, where X is the greatest power among creatures you control.

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters tapped unless you control two or more basic lands.

Llanowar Elves

Skarrg Guildmage

{R}{G}: Creatures you control gain trample until end of turn.
{1}{R}{G}: Target land you control becomes a 4/4 Elemental creature until end of turn. It's still a land.

Forest

Blossoming Defense

Target creature you control gets +2/+2 and gains hexproof until end of turn.

Mountain

Furnace Reins

Gain control of target creature until end of turn. Untap that creature. Until end of turn, it gains haste and "Whenever this creature deals combat damage to a player or battle, create a Treasure token." (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Owlbear

Trample
Keen Senses — When Owlbear enters, draw a card.

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.

Dragon Hatchling

Flying
{R}: Dragon Hatchling gets +1/+0 until end of turn.

Signal the Clans

Search your library for three creature cards and reveal them. If you reveal three cards with different names, choose one of them at random and put that card into your hand. Shuffle the rest into your library.

Jaxis, the Troublemaker

{R}, {T}, Discard a card: Create a token that's a copy of another target creature you control. It gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step. Activate only as a sorcery.
Blitz {1}{R} (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.)

Moonrise Intruder

Menace (This creature can't be blocked except by two or more creatures.)
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Moonrise Intruder.

Village Messenger

Haste
At the beginning of each upkeep, if no spells were cast last turn, transform Village Messenger.