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.

Ram Through

Target creature you control deals damage equal to its power to target creature you don't control. If the creature you control has trample, excess damage is dealt to that creature's controller instead.

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

You Look Upon the Tarrasque

Choose one —
• Run and Hide — Prevent all combat damage that would be dealt to you and creatures you control this turn.
• Gather Your Courage — Target creature gets +5/+5 and gains indestructible until end of turn. All creatures your opponents control able to block that creature this turn do so.

Nissa, Who Shakes the World

Whenever you tap a Forest for mana, add an additional {G}.
+1: Put three +1/+1 counters on up to one target noncreature land you control. Untap it. It becomes a 0/0 Elemental creature with vigilance and haste that's still a land.
−8: You get an emblem with "Lands you control have indestructible." Search your library for any number of Forest cards, put them onto the battlefield tapped, then shuffle.

Toski, Bearer of Secrets

This spell can't be countered.
Indestructible
Toski, Bearer of Secrets attacks each combat if able.
Whenever a creature you control deals combat damage to a player, draw a card.

Blossoming Defense

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

Pathbreaker Ibex

Whenever Pathbreaker Ibex attacks, creatures you control gain trample and get +X/+X until end of turn, where X is the greatest power among creatures you control.

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.

Treefolk Umbra

Enchant creature
Enchanted creature gets +0/+2 and assigns combat damage equal to its toughness rather than its power.
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Alpha Status

Enchant creature
Enchanted creature gets +2/+2 for each other creature on the battlefield that shares a creature type with it.

Undergrowth Recon

At the beginning of your upkeep, return target land card from your graveyard to the battlefield tapped.

Seton's Desire

Enchant creature
Enchanted creature gets +2/+2.
Threshold — As long as seven or more cards are in your graveyard, all creatures able to block enchanted creature do so.

Blanchwood Armor

Enchant creature
Enchanted creature gets +1/+1 for each Forest you control.

Vitalize

Snake Umbra

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals damage to an opponent, you may draw a card."
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Boar Umbra

Enchant creature
Enchanted creature gets +3/+3.
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Roar of Challenge

All creatures able to block target creature this turn do so.
Ferocious — That creature gains indestructible until end of turn if you control a creature with power 4 or greater.

Mobilize

Ohran Frostfang

Attacking creatures you control have deathtouch.
Whenever a creature you control deals combat damage to a player, draw a card.

Darksteel Citadel

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Seeds of Innocence

Destroy all artifacts. They can't be regenerated. The controller of each of those artifacts gains life equal to its mana value.

Erinis, Gloom Stalker

Deathtouch
Whenever Erinis, Gloom Stalker attacks, return target land card from your graveyard to the battlefield.
Choose a Background (You can have a Background as a second commander.)

Bear Umbra

Enchant creature
Enchanted creature gets +2/+2 and has "Whenever this creature attacks, untap all lands you control."
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Creeping Corrosion

Garruk, Primal Hunter

+1: Create a 3/3 green Beast creature token.
−3: Draw cards equal to the greatest power among creatures you control.
−6: Create a 6/6 green Wurm creature token for each land you control.

Garruk Wildspeaker

+1: Untap two target lands.
−1: Create a 3/3 green Beast creature token.
−4: Creatures you control get +3/+3 and gain trample until end of turn.

Season of Growth

Whenever a creature enters the battlefield under your control, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)
Whenever you cast a spell that targets a creature you control, draw a card.

Irresistible Prey

Target creature must be blocked this turn if able.
Draw a card.

Rishkar's Expertise

Draw cards equal to the greatest power among creatures you control.
You may cast a spell with mana value 5 or less from your hand without paying its mana cost.

Alpha Authority

Enchant creature
Enchanted creature has hexproof and can't be blocked by more than one creature.

Snow-Covered Forest

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Contest of Claws

Target creature you control deals damage equal to its power to another target creature. If excess damage was dealt this way, discover X, where X is that excess damage. (Exile cards from the top of your library until you exile a nonland card with that mana value or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Ramunap Excavator

Refresh

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Nissa, Worldwaker

+1: Target land you control becomes a 4/4 Elemental creature with trample. It's still a land.
+1: Untap up to four target Forests.
−7: Search your library for any number of basic land cards, put them onto the battlefield, then shuffle. Those lands become 4/4 Elemental creatures with trample. They're still lands.

Hard-Hitting Question

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

Into the North

Search your library for a snow land card, put it onto the battlefield tapped, then shuffle.

Blossoming Tortoise

Whenever Blossoming Tortoise enters the battlefield or attacks, mill three cards, then return a land card from your graveyard to the battlefield tapped.
Activated abilities of lands you control cost {1} less to activate.
Land creatures you control get +1/+1.

Glimpse the Core

Choose one —
• Search your library for a basic Forest card, put that card onto the battlefield tapped, then shuffle.
• Return target Cave card from your graveyard to the battlefield tapped.

Roiling Regrowth

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on Beastmaster Ascension.
As long as Beastmaster Ascension has seven or more quest counters on it, creatures you control get +5/+5.

Ancestral Mask

Enchant creature
Enchanted creature gets +2/+2 for each other enchantment on the battlefield.

Yavimaya, Cradle of Growth

Each land is a Forest in addition to its other land types.

Misty Rainforest

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Emergent Sequence

Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. That land becomes a 0/0 green and blue Fractal creature that's still a land. Put a +1/+1 counter on it for each land you had enter the battlefield under your control this turn.

Thunderfoot Baloth

Trample
Lieutenant — As long as you control your commander, Thunderfoot Baloth gets +2/+2 and other creatures you control get +2/+2 and have trample.

Windswept Heath

{T}, Pay 1 life, Sacrifice Windswept Heath: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Prismatic Vista

{T}, Pay 1 life, Sacrifice Prismatic Vista: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Sixth Sense

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, you may draw a card."

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Benefactor's Draught

Untap all creatures. Until end of turn, whenever a creature an opponent controls blocks, draw a card.
Draw a card.

Setessan Training

Enchant creature you control
When Setessan Training enters the battlefield, draw a card.
Enchanted creature gets +1/+0 and has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Spider Umbra

Enchant creature
Enchanted creature gets +1/+1 and has reach. (It can block creatures with flying.)
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Scavenger Grounds

{T}: Add {C}.
{2}, {T}, Sacrifice a Desert: Exile all graveyards.

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Blizzard Brawl

Choose target creature you control and target creature you don't control. If you control three or more snow permanents, the creature you control gets +1/+0 and gains indestructible until end of turn. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Entish Restoration

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If you control a creature with power 4 or greater, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Rune of Might

Enchant permanent
When Rune of Might enters the battlefield, draw a card.
As long as enchanted permanent is a creature, it gets +1/+1 and has trample.
As long as enchanted permanent is an Equipment, it has "Equipped creature gets +1/+1 and has trample."

Vesuva

You may have Vesuva enter the battlefield tapped as a copy of any land on the battlefield.

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Savage Punch

Target creature you control fights target creature you don't control.
Ferocious — The creature you control gets +2/+2 until end of turn before it fights if you control a creature with power 4 or greater.

Hunter's Insight

Choose target creature you control. Whenever that creature deals combat damage to a player or planeswalker this turn, draw that many cards.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Blighted Woodland

{T}: Add {C}.
{3}{G}, {T}, Sacrifice Blighted Woodland: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Pit of Offerings

Pit of Offerings enters the battlefield tapped.
When Pit of Offerings enters the battlefield, exile up to three target cards from graveyards.
{T}: Add {C}.
{T}: Add one mana of any of the exiled cards' colors.

Warriors' Lesson

Until end of turn, up to two target creatures you control each gain "Whenever this creature deals combat damage to a player, draw a card."

Anthousa, Setessan Hero

Heroic — Whenever you cast a spell that targets Anthousa, Setessan Hero, up to three target lands you control each become 2/2 Warrior creatures until end of turn. They're still lands.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Hunter's Prowess

Until end of turn, target creature gets +3/+3 and gains trample and "Whenever this creature deals combat damage to a player, draw that many cards."

Tail Swipe

Choose target creature you control and target creature you don't control. If you cast this spell during your main phase, the creature you control gets +1/+1 until end of turn. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Pick Your Poison

Choose one —
• Each opponent sacrifices an artifact.
• Each opponent sacrifices an enchantment.
• Each opponent sacrifices a creature with flying.

Ruinous Intrusion

Exile target artifact or enchantment. Put X +1/+1 counters on target creature you control, where X is the mana value of the permanent exiled this way.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Keen Sense

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Soul's Majesty

Draw cards equal to the power of target creature you control.

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.

Scavenging Ooze

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on Scavenging Ooze and you gain 1 life.

Harvest Season

Search your library for up to X basic land cards, where X is the number of tapped creatures you control, put those cards onto the battlefield tapped, then shuffle.

Tyvar's Stand

Target creature you control gets +X/+X and gains hexproof and indestructible until end of turn. (A creature with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)