Strength-Testing Hammer

Whenever equipped creature attacks, roll a six-sided die. That creature gets +X/+0 until end of turn, where X is the result. Then if it has the greatest power or is tied for greatest power among creatures on the battlefield, draw a card.
Equip {3}

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Runechanter's Pike

Equipped creature has first strike and gets +X/+0, where X is the number of instant and sorcery cards in your graveyard.
Equip {2}

Surge to Victory

Exile target instant or sorcery card from your graveyard. Creatures you control get +X/+0 until end of turn, where X is that card's mana value. Whenever a creature you control deals combat damage to a player this turn, copy the exiled card. You may cast the copy without paying its mana cost.

Hardy Outlander

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, another target creature you control gets +X/+X until end of turn, where X is this creature's power."

Rampant Growth

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

Mana Geyser

Add {R} for each tapped land your opponents control.

Iron-Craw Crusher

Prototype {2}{G}{G} — 2/5 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Whenever Iron-Craw Crusher attacks, target attacking creature gets +X/+0 until end of turn, where X is Iron-Craw Crusher's power.

Dragon Throne of Tarkir

Equipped creature has defender and "{2}, {T}: Other creatures you control gain trample and get +X/+X until end of turn, where X is this creature's power."
Equip {3}

Surge of Strength

As an additional cost to cast this spell, discard a red or green card.
Target creature gains trample and gets +X/+0 until end of turn, where X is that creature's mana value.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample

Not of This World

Counter target spell or ability that targets a permanent you control.
This spell costs {7} less to cast if it targets a spell or ability that targets a creature you control with power 7 or greater.

Greater Good

Sacrifice a creature: Draw cards equal to the sacrificed creature's power, then discard three cards.

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.

Garruk's Uprising

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.)
Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

Wine of Blood and Iron

{4}: Target creature gets +X/+0 until end of turn, where X is its power. Sacrifice Wine of Blood and Iron at the beginning of the next end step.

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.)

Copperline Gorge

Copperline Gorge enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {R} or {G}.

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.

Shapers' Sanctuary

Whenever a creature you control becomes the target of a spell or ability an opponent controls, you may draw a card.

Elturel Survivors

Trample, myriad
As long as Elturel Survivors is attacking, it gets +X/+0, where X is the number of lands defending player controls.

Temple of the False God

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

Quartzwood Crasher

Trample
Whenever one or more creatures you control with trample deal combat damage to a player, create an X/X green Dinosaur Beast creature token with trample, where X is the amount of damage those creatures dealt to that player.

Ferocity of the Wilds

Attacking non-Human creatures you control get +1/+0 and have trample.

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.

Livaan, Cultist of Tiamat

Whenever you cast a noncreature spell, target creature gets +X/+0 until end of turn, where X is that spell's mana value.
Choose a Background (You can have a Background as a second commander.)

Dragon Breath

Enchant creature
Enchanted creature has haste.
{R}: Enchanted creature gets +1/+0 until end of turn.
When a creature with mana value 6 or greater enters the battlefield, you may return Dragon Breath from your graveyard to the battlefield attached to that creature.

Fatal Frenzy

Until end of turn, target creature you control gains trample and gets +X/+0, where X is its power. Sacrifice it at the beginning of the next end step.

Glorious Sunrise

At the beginning of combat on your turn, choose one —
• Creatures you control get +1/+1 and gain trample until end of turn.
• Target land gains "{T}: Add {G}{G}{G}" until end of turn.
• Draw a card if you control a creature with power 3 or greater.
• You gain 3 life.

Neyith of the Dire Hunt

Whenever one or more creatures you control fight or become blocked, draw a card.
At the beginning of combat on your turn, you may pay {2}{R/G}. If you do, double target creature's power until end of turn. That creature must be blocked this combat if able. ({R/G} can be paid with either {R} or {G}.)

Bronze Cudgels

{2}: Until end of turn, equipped creature gets +X/+0, where X is the number of times this ability has resolved this turn.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Enrage

Target creature gets +X/+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.

Mosswort Bridge

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Mosswort Bridge enters the battlefield tapped.
{T}: Add {G}.
{G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

Barbed Battlegear

Freelance Muscle

Whenever Freelance Muscle attacks or blocks, it gets +X/+X until end of turn, where X is the greatest power and/or toughness among other creatures you control.

Moraug, Fury of Akoum

Each creature you control gets +1/+0 for each time it has attacked this turn.
Landfall — Whenever a land enters the battlefield under your control, if it's your main phase, there's an additional combat phase after this phase. At the beginning of that combat, untap all creatures you control.

Ghitu Firebreathing

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
{R}: Enchanted creature gets +1/+0 until end of turn.
{R}: Return Ghitu Firebreathing to its owner's hand.

Mountain

Zhur-Taa Ancient

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

Burning Anger

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

Zilortha, Strength Incarnate

Trample
Lethal damage dealt to creatures you control is determined by their power rather than their toughness.

Tribute to the World Tree

Whenever a creature enters the battlefield under your control, draw a card if its power is 3 or greater. Otherwise, put two +1/+1 counters on it.

Fiery Mantle

Enchant creature
{R}: Enchanted creature gets +1/+0 until end of turn.
When Fiery Mantle is put into a graveyard from the battlefield, return Fiery Mantle to its owner's hand.

Elemental Bond

Whenever a creature with power 3 or greater enters the battlefield under your control, draw a card.

Bonders' Enclave

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

Soul's Majesty

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

Impelled Giant

Trample
Tap an untapped red creature you control other than Impelled Giant: Impelled Giant gets +X/+0 until end of turn, where X is the power of the creature tapped this way.

Chandra's Ignition

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

Unleash Fury

Double the power of target creature until end of turn.

Feral Animist

{3}: Feral Animist gets +X/+0 until end of turn, where X is its power.

Crown of Flames

Enchant creature
{R}: Enchanted creature gets +1/+0 until end of turn.
{R}: Return Crown of Flames to its owner's hand.

Terramorphic Expanse

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

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.

Temple of Abandon

Temple of Abandon enters the battlefield tapped.
When Temple of Abandon enters the battlefield, scry 1.
{T}: Add {R} or {G}.

Thunderblust

Haste
Thunderblust has trample as long as it has a -1/-1 counter on it.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Wilderness Reclamation

At the beginning of your end step, untap all lands you control.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Kodama's Reach

Tuya Bearclaw

Whenever Tuya Bearclaw attacks, it gets +X/+X until end of turn, where X is the greatest power among other creatures you control.

Berserk

Cast this spell only before the combat damage step.
Target creature gains trample and gets +X/+0 until end of turn, where X is its power. At the beginning of the next end step, destroy that creature if it attacked this turn.

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.)

Mana Flare

In Search of Greatness

At the beginning of your upkeep, you may cast a permanent spell from your hand with mana value equal to 1 plus the highest mana value among other permanents you control without paying its mana cost. If you don't, scry 1.

Yew Spirit

{2}{G}{G}: Yew Spirit gets +X/+X until end of turn, where X is its power.

Evolving Wilds

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

Fiery Emancipation

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

Siege Behemoth

Hexproof
As long as Siege Behemoth is attacking, for each creature you control, you may have that creature assign its combat damage as though it weren't blocked.

City on Fire

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.

Mishra's Command

Choose two —
• Choose target player. They may discard up to X cards. Then they draw a card for each card discarded this way.
• This spell deals X damage to target creature.
• This spell deals X damage to target planeswalker.
• Target creature gets +X/+0 and gains haste until end of turn.

Arni Slays the Troll

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Target creature you control fights up to one target creature you don't control.
II — Add {R}. Put two +1/+1 counters on up to one target creature you control.
III — You gain life equal to the greatest power among creatures you control.

Forest

Gratuitous Violence

If a creature you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Arcane Signet

Lunar Frenzy

Target creature you control gets +X/+0 and gains first strike and trample until end of turn.

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.

Luxurious Libation

Target creature gets +X/+X until end of turn. Create a 1/1 green and white Citizen creature token.

Rush of Blood

Target creature gets +X/+0 until end of turn, where X is its power.

Arni Brokenbrow

Haste
Boast — {1}: You may change Arni Brokenbrow's base power to 1 plus the greatest power among other creatures you control until end of turn. (Activate only if this creature attacked this turn and only once each turn.)

Colossal Majesty

At the beginning of your upkeep, if you control a creature with power 4 or greater, draw a card.

Wild Beastmaster

Whenever Wild Beastmaster attacks, each other creature you control gets +X/+X until end of turn, where X is Wild Beastmaster's power.

Kessig Wolf Run

{T}: Add {C}.
{X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

Cinder Glade

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

Concord with the Kami

At the beginning of your end step, choose one or more —
• Put a +1/+1 counter on target creature with a counter on it.
• Draw a card if you control an enchanted creature.
• Create a 1/1 colorless Spirit creature token if you control an equipped creature.

Untamed Might

Target creature gets +X/+X until end of turn.

Colossification

Enchant creature
When Colossification enters the battlefield, tap enchanted creature.
Enchanted creature gets +20/+20.

Mana Reflection

If you tap a permanent for mana, it produces twice as much of that mana instead.

Primal Might

Target creature you control gets +X/+X until end of turn. Then it fights up to one target creature you don't control.

Skarrg, the Rage Pits

{T}: Add {C}.
{R}{G}, {T}: Target creature gets +1/+1 and gains 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.

Exponential Growth

Until end of turn, double target creature's power X times.

Family's Favor

Whenever you attack, put a shield counter on target attacking creature. Until end of turn, it gains "Whenever this creature deals combat damage to a player, remove a shield counter from it. If you do, draw a card." (If a creature with a shield counter on it would be dealt damage or destroyed, remove a shield counter from it instead.)

Spinerock Knoll

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Spinerock Knoll enters the battlefield tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.

Sol Ring

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Withstand Death

Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it's still put into its owner's graveyard.)

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Verdant Mastery

You may pay {3}{G} rather than pay this spell's mana cost.
Search your library for up to four basic land cards and reveal them. Put one of them onto the battlefield tapped under an opponent's control if the {3}{G} cost was paid. Put two of them onto the battlefield tapped under your control and the rest into your hand. Then shuffle.

Balduvian Rage

Target attacking creature gets +X/+0 until end of turn.
Draw a card at the beginning of the next turn's upkeep.