Archetype of Aggression

Creatures you control have trample.
Creatures your opponents control lose trample and can't have or gain trample.

Polukranos, World Eater

{X}{X}{G}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
When Polukranos, World Eater becomes monstrous, it deals X damage divided as you choose among any number of target creatures your opponents control. Each of those creatures deals damage equal to its power to Polukranos.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Sudden Demise

Choose a color. Sudden Demise deals X damage to each creature of the chosen color.

Arashi, the Sky Asunder

{X}{G}, {T}: Arashi, the Sky Asunder deals X damage to target creature with flying.
Channel — {X}{G}{G}, Discard Arashi: Arashi deals X damage to each creature with flying.

Warstorm Surge

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

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.

Swarmborn Giant

When you're dealt combat damage, sacrifice Swarmborn Giant.
{4}{G}{G}: Monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)
As long as Swarmborn Giant is monstrous, it has reach.

Oran-Rief Hydra

Trample
Landfall — Whenever a land you control enters, put a +1/+1 counter on Oran-Rief Hydra. If that land is a Forest, put two +1/+1 counters on Oran-Rief Hydra instead.

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.

Game Trail

As Game Trail enters, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters tapped.
{T}: Add {R} or {G}.

Nessian Wilds Ravager

Tribute 6 (As this creature enters, an opponent of your choice may put six +1/+1 counters on it.)
When Nessian Wilds Ravager enters, if tribute wasn't paid, you may have Nessian Wilds Ravager fight another target creature. (Each deals damage equal to its power to the other.)

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.)

Momentous Fall

As an additional cost to cast this spell, sacrifice a creature.
You draw cards equal to the sacrificed creature's power, then you gain life equal to its toughness.

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.

Voracious Hydra

Trample
Voracious Hydra enters with X +1/+1 counters on it.
When Voracious Hydra enters, choose one —
• Double the number of +1/+1 counters on Voracious Hydra.
• Voracious Hydra fights target creature you don't control.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

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.

Haunted Cloak

Equipped creature has vigilance, trample, and haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Silklash Spider

Reach
{X}{G}{G}: Silklash Spider deals X damage to each creature with flying.

Predatory Urge

Enchant creature
Enchanted creature has "{T}: This creature deals damage equal to its power to target creature. That creature deals damage equal to its power to this creature."

Xenagos, God of Revels

Indestructible
As long as your devotion to red and green is less than seven, Xenagos isn't a creature.
At the beginning of combat on your turn, another target creature you control gains haste and gets +X/+X until end of turn, where X is that creature's power.

Soulblast

As an additional cost to cast this spell, sacrifice all creatures you control.
Soulblast deals damage to any target equal to the total power of the sacrificed creatures.

Unwilling Recruit

Gain control of target creature until end of turn. Untap that creature. It gets +X/+0 and gains haste until end of turn.

Taiga

Contested Cliffs

{T}: Add {C}.
{R}{G}, {T}: Target Beast creature you control fights target creature an opponent controls. (Each deals damage equal to its power to the other.)

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

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.

Animist's Awakening

Reveal the top X cards of your library. Put all land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap those lands.

Gruul War Chant

Attacking creatures you control get +1/+0 and have menace.

Sol Ring

Elemental Bond

Whenever a creature you control with power 3 or greater enters, draw a card.

Mistcutter Hydra

This spell can't be countered.
Haste, protection from blue
Mistcutter Hydra enters with X +1/+1 counters on it.

Rolling Thunder

Rolling Thunder deals X damage divided as you choose among any number of targets.

Flowstone Slide

All creatures get +X/-X until end of turn.

Keeper of Progenitus

Whenever a player taps a Mountain, Forest, or Plains for mana, that player adds one mana of any type that land produced.

Sakiko, Mother of Summer

Whenever a creature you control deals combat damage to a player, add that much {G}. Until end of turn, you don't lose this mana as steps and phases end.

Canopy Cover

Enchant creature
Enchanted creature can't be blocked except by creatures with flying or reach.
Enchanted creature can't be the target of spells or abilities your opponents control.

Dangerous

All creatures able to block target creature this turn do so.
Fuse (You may cast one or both halves of this card from your hand.)

Armed

Target creature gets +1/+1 and gains double strike until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

Armed // Dangerous

Death's Presence

Whenever a creature you control dies, put X +1/+1 counters on target creature you control, where X is the power of the creature that died.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Starstorm

Starstorm deals X damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Burning Anger

Enchant creature
Enchanted creature has "{T}: This creature deals damage equal to its power to any target."

Fire-Lit Thicket

{T}: Add {C}.
{R/G}, {T}: Add {R}{R}, {R}{G}, or {G}{G}.

Scourge of Skola Vale

Trample
Scourge of Skola Vale enters with two +1/+1 counters on it.
{T}, Sacrifice another creature: Put a number of +1/+1 counters on Scourge of Skola Vale equal to the sacrificed creature's toughness.

Steelbane Hydra

Steelbane Hydra enters with X +1/+1 counters on it.
{2}{G}, Remove a +1/+1 counter from Steelbane Hydra: Destroy target artifact or enchantment.

Manaplasm

Whenever you cast a spell, Manaplasm gets +X/+X until end of turn, where X is that spell's mana value.

Sigil of Distinction

Sigil of Distinction enters with X charge counters on it.
Equipped creature gets +1/+1 for each charge counter on Sigil of Distinction.
Equip—Remove a charge counter from Sigil of Distinction.

Skarrg, the Rage Pits

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

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.

Kalonian Hydra

Trample
Kalonian Hydra enters with four +1/+1 counters on it.
Whenever Kalonian Hydra attacks, double the number of +1/+1 counters on each creature you control.

Savageborn Hydra

Double strike
Savageborn Hydra enters with X +1/+1 counters on it.
{1}{R/G}: Put a +1/+1 counter on Savageborn Hydra. Activate only as a sorcery.

Commune with Lava

Exile the top X cards of your library. Until the end of your next turn, you may play those cards.

Savage Ventmaw

Flying
Whenever this creature attacks, add {R}{R}{R}{G}{G}{G}. Until end of turn, you don't lose this mana as steps and phases end.

Rootbound Crag

Rootbound Crag enters tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

Primordial Hydra

Primordial Hydra enters with X +1/+1 counters on it.
At the beginning of your upkeep, double the number of +1/+1 counters on Primordial Hydra.
Primordial Hydra has trample as long as it has ten or more +1/+1 counters on it.

Archetype of Endurance

Creatures you control have hexproof.
Creatures your opponents control lose hexproof and can't have or gain hexproof.

Zendikar Resurgent

Whenever you tap a land for mana, add one mana of any type that land produced. (The types of mana are white, blue, black, red, green, and colorless.)
Whenever you cast a creature spell, draw a card.

Hydra Omnivore

Whenever Hydra Omnivore deals combat damage to an opponent, it deals that much damage to each other opponent.

Triumph of Ferocity

At the beginning of your upkeep, draw a card if you control the creature with the greatest power or tied for the greatest power.

Primal Vigor

If one or more tokens would be created, twice that many of those tokens are created instead.
If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Apocalypse Hydra

Apocalypse Hydra enters with X +1/+1 counters on it. If X is 5 or more, it enters with an additional X +1/+1 counters on it.
{1}{R}, Remove a +1/+1 counter from Apocalypse Hydra: It deals 1 damage to any target.

Clan Defiance

Choose one or more —
• Clan Defiance deals X damage to target creature with flying.
• Clan Defiance deals X damage to target creature without flying.
• Clan Defiance deals X damage to target player or planeswalker.

Mountain

Gelatinous Genesis

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Rosheen Meanderer

{T}: Add {C}{C}{C}{C}. Spend this mana only on costs that contain {X}.

Astral Cornucopia

Astral Cornucopia enters with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Mossfire Valley

Bellowing Tanglewurm

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Other green creatures you control have intimidate.

Fervor

Creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

Outmaneuver

X target blocked creatures assign their combat damage this turn as though they weren't blocked.

Gruul Turf

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

Crater's Claws

Crater's Claws deals X damage to any target.
Ferocious — Crater's Claws deals X plus 2 damage instead if you control a creature with power 4 or greater.

Gather the Pack

Reveal the top five cards of your library. You may put a creature card from among them into your hand. Put the rest into your graveyard.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, put up to two creature cards from among the revealed cards into your hand instead of one.

Cinder Glade

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

Flameblast Dragon

Flying
Whenever Flameblast Dragon attacks, you may pay {X}{R}. If you do, Flameblast Dragon deals X damage to any target.

Forest

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.