Humble Naturalist

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Forest

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.)

Genesis Hydra

When you cast this spell, reveal the top X cards of your library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield. Then shuffle the rest into your library.
Genesis Hydra enters with X +1/+1 counters on it.

Evolving Wilds

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

Biogenic Upgrade

Distribute three +1/+1 counters among one, two, or three target creatures, then double the number of +1/+1 counters on each of those creatures.

Phyrexia's Core

{T}: Add {C}.
{1}, {T}, Sacrifice an artifact: You gain 1 life.

Pulse of Murasa

Return target creature or land card from a graveyard to its owner's hand. You gain 6 life.

Scaled Herbalist

{T}: You may put a land card from your hand onto the battlefield.

Lifeblood Hydra

Trample
Lifeblood Hydra enters with X +1/+1 counters on it.
When Lifeblood Hydra dies, you gain life and draw cards equal to its power.

Phyrexian Swarmlord

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
At the beginning of your upkeep, create a 1/1 green Phyrexian Insect creature token with infect for each poison counter your opponents have.

Heroes' Bane

This creature enters with four +1/+1 counters on it.
{2}{G}{G}: Put X +1/+1 counters on this creature, where X is its power.

Hungering Hydra

Hungering Hydra enters with X +1/+1 counters on it.
Hungering Hydra can't be blocked by more than one creature.
Whenever Hungering Hydra is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

Ironscale Hydra

If a creature would deal combat damage to Ironscale Hydra, prevent that damage and put a +1/+1 counter on Ironscale Hydra.

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Vastwood Hydra

Vastwood Hydra enters with X +1/+1 counters on it.
When Vastwood Hydra dies, you may distribute a number of +1/+1 counters equal to the number of +1/+1 counters on Vastwood Hydra among any number of creatures you control.

Fierce Empath

When this creature enters, you may search your library for a creature card with mana value 6 or greater, reveal it, put it into your hand, then shuffle.

Thriving Moor

Thriving Moor enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Defend the Celestus

Distribute three +1/+1 counters among one, two, or three target creatures you control.

Hydra Broodmaster

{X}{X}{G}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
When Hydra Broodmaster becomes monstrous, create X X/X green Hydra creature tokens.

Slippery Karst

Slippery Karst enters tapped.
{T}: Add {G}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Prosthetic Injector

Equipped creature gets +0/+2 and has toxic 1. (Players dealt combat damage by equipped creature also get a poison counter.)
Equip {1}

Wren's Run Hydra

Reach
Wren's Run Hydra enters with X +1/+1 counters on it.
Reinforce X—{X}{G}{G} ({X}{G}{G}, Discard this card: Put X +1/+1 counters on target creature.)

Llanowar Visionary

When Llanowar Visionary enters, draw a card.
{T}: Add {G}.

You Happen On a Glade

Choose one —
• Journey On — Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.
• Make Camp — Return target permanent card from your graveyard to your hand.

Plague Nurse

Toxic 2
{2}{G}: Each other creature you control with toxic gains toxic 1 until end of turn. Activate only once each turn. (A player dealt combat damage by a creature with toxic also gets poison counters equal to that creature's total toxic value.)

Golgari Guildgate

This land enters tapped.
{T}: Add {B} or {G}.

Jungle Delver

{3}{G}: Put a +1/+1 counter on Jungle Delver.

Unknown Shores

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Pelt Collector

Whenever another creature you control enters or dies, if that creature's power is greater than Pelt Collector's, put a +1/+1 counter on Pelt Collector.
As long as Pelt Collector has three or more +1/+1 counters on it, it has trample.

Unnatural Restoration

Return target permanent card from your graveyard to your hand. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Gargos, Vicious Watcher

Vigilance
Hydra spells you cast cost {4} less to cast.
Whenever a creature you control becomes the target of a spell, Gargos, Vicious Watcher fights up to one target creature you don't control.

Invigorating Surge

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on that creature.

Witherbloom Campus

Witherbloom Campus enters tapped.
{T}: Add {B} or {G}.
{4}, {T}: Scry 1.

Rabid Bite

Target creature you control deals damage equal to its power to target creature you don't control.

Shrine of Boundless Growth

At the beginning of your upkeep and whenever you cast a green spell, put a charge counter on Shrine of Boundless Growth.
{T}, Sacrifice Shrine of Boundless Growth: Add {C} for each charge counter on Shrine of Boundless Growth.

Golgari Rot Farm

Golgari Rot Farm enters tapped.
When Golgari Rot Farm enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.