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.

Ichor Explosion

As an additional cost to cast this spell, sacrifice a creature.
All creatures get -X/-X until end of turn, where X is the sacrificed creature's power.

Fungal Sprouting

Create X 1/1 green Saproling creature tokens, where X is the greatest power among creatures you control.

Ooze Garden

{1}{G}, Sacrifice a non-Ooze creature: Create an X/X green Ooze creature token, where X is the sacrificed creature's power. Activate only as a sorcery.

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.

God-Eternal Rhonas

Deathtouch
When God-Eternal Rhonas enters the battlefield, double the power of each other creature you control until end of turn. Those creatures gain vigilance until end of turn.
When God-Eternal Rhonas dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Phyrexian Dreadnought

Trample
When Phyrexian Dreadnought enters the battlefield, sacrifice it unless you sacrifice any number of creatures with total power 12 or greater.

Traverse the Outlands

Search your library for up to X basic land cards, where X is the greatest power among creatures you control. Put those cards onto the battlefield tapped, then shuffle.

Infernal Reckoning

Exile target colorless creature. You gain life equal to its power.

Carrion

As an additional cost to cast this spell, sacrifice a creature.
Create X 0/1 black Insect creature tokens, where X is the sacrificed creature's power.

Soul's Might

Put X +1/+1 counters on target creature, where X is that creature's power.

Tanuki Transplanter

Whenever Tanuki Transplanter or equipped creature attacks, add an amount of {G} equal to its power. Until end of turn, you don't lose this mana as steps and phases end.
Reconfigure {3} ({3}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Saw in Half

Destroy target creature. If that creature dies this way, its controller creates two tokens that are copies of that creature, except their base power is half that creature's power and their base toughness is half that creature's toughness. Round up each time.

Essence Harvest

Target player loses X life and you gain X life, where X is the greatest power among creatures you control.

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.

Ghoulcaller Gisa

{B}, {T}, Sacrifice another creature: Create X 2/2 black Zombie creature tokens, where X is the sacrificed creature's power.

Mask of Griselbrand

Equipped creature has flying and lifelink.
Whenever equipped creature dies, you may pay X life, where X is its power. If you do, draw X cards.
Equip {3}

Mossbridge Troll

If Mossbridge Troll would be destroyed, regenerate it.
Tap any number of untapped creatures you control other than Mossbridge Troll with total power 10 or greater: Mossbridge Troll gets +20/+20 until end of turn.

Unnatural Growth

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Reign of the Pit

Each player sacrifices a creature. Create an X/X black Demon creature token with flying, where X is the total power of the creatures sacrificed this way.

Prime Speaker Zegana

Prime Speaker Zegana enters the battlefield with X +1/+1 counters on it, where X is the greatest power among other creatures you control.
When Prime Speaker Zegana enters the battlefield, draw cards equal to its power.

Raised by Giants

Commander creatures you own have base power and toughness 10/10 and are Giants in addition to their other types.

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.

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.

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.

Tormented Thoughts

As an additional cost to cast this spell, sacrifice a creature.
Target player discards a number of cards equal to the sacrificed creature's power.

Greater Good

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

Nantuko Mentor

{2}{G}, {T}: Target creature gets +X/+X until end of turn, where X is that creature's power.

Soul's Majesty

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

Surestrike Trident

Equipped creature has first strike and "{T}, Unattach Surestrike Trident: This creature deals damage equal to its power to target player or planeswalker."
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Rite of Consumption

As an additional cost to cast this spell, sacrifice a creature.
Rite of Consumption deals damage equal to the sacrificed creature's power to target player or planeswalker. You gain life equal to the damage dealt this way.

Life's Legacy

As an additional cost to cast this spell, sacrifice a creature.
Draw cards equal to the sacrificed creature's power.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

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.

Dying Wish

Enchant creature you control
When enchanted creature dies, target player loses X life and you gain X life, where X is its power.

Zopandrel, Hunger Dominus

Reach
At the beginning of each combat, double the power and toughness of each creature you control until end of turn.
{G/P}{G/P}, Sacrifice two other creatures: Put an indestructible counter on Zopandrel, Hunger Dominus. ({G/P} can be paid with either {G} or 2 life.)

Final Strike

As an additional cost to cast this spell, sacrifice a creature.
Final Strike deals damage to target opponent or planeswalker equal to the sacrificed creature's power.

Twisted Justice

Target player sacrifices a creature. You draw cards equal to that creature's power.

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."

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.

Miming Slime

Create an X/X green Ooze creature token, where X is the greatest power among creatures you control.

One with the Kami

Flash
Enchant creature you control
Whenever enchanted creature or another modified creature you control dies, create X 1/1 colorless Spirit creature tokens, where X is that creature's power. (Equipment, Auras you control, and counters are modifications.)

Exponential Growth

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

Tend the Pests

As an additional cost to cast this spell, sacrifice a creature.
Create X 1/1 black and green Pest creature tokens with "When this creature dies, you gain 1 life," where X is the sacrificed creature's power.

Sword of the Ages

Sword of the Ages enters the battlefield tapped.
{T}, Sacrifice Sword of the Ages and any number of creatures you control: Sword of the Ages deals X damage to any target, where X is the total power of the creatures sacrificed this way, then exile Sword of the Ages and those creature cards.

Choose Your Weapon

Choose one —
• Two-Weapon Fighting — Double target creature's power and toughness until end of turn.
• Archery — This spell deals 5 damage to target creature with flying.

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}

Xathrid Demon

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than Xathrid Demon, then each opponent loses life equal to the sacrificed creature's power. If you can't sacrifice a creature, tap Xathrid Demon and you lose 7 life.

Predator's Rapport

Choose target creature you control. You gain life equal to that creature's power plus its toughness.

Jarad, Golgari Lich Lord

Jarad, Golgari Lich Lord gets +1/+1 for each creature card in your graveyard.
{1}{B}{G}, Sacrifice another creature: Each opponent loses life equal to the sacrificed creature's power.
Sacrifice a Swamp and a Forest: Return Jarad from your graveyard to your hand.

Keldon Battlewagon

Trample
Keldon Battlewagon can't block.
When Keldon Battlewagon attacks, sacrifice it at end of combat.
Tap an untapped creature you control: Keldon Battlewagon gets +X/+0 until end of turn, where X is the power of the creature tapped this way.

Return of the Wildspeaker

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Astarion's Thirst

Exile target creature. Put X +1/+1 counters on a commander creature you control, where X is the power of the creature exiled this way.

Winged Temple of Orazca

(Transforms from Hadana's Climb.)
{T}: Add one mana of any color.
{1}{G}{U}, {T}: Target creature you control gains flying and gets +X/+X until end of turn, where X is its power.

Hadana's Climb

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has three or more +1/+1 counters on it, transform Hadana's Climb.

Hadana's Climb // Winged Temple of Orazca

Phyrexian Ingester

Imprint — When Phyrexian Ingester enters the battlefield, you may exile target nontoken creature.
Phyrexian Ingester gets +X/+Y, where X is the exiled creature card's power and Y is its toughness.

Doom Weaver

Reach
Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
As long as Doom Weaver is paired with another creature, each of those creatures has "When this creature dies, draw cards equal to its power."

Nylea's Colossus

Constellation — Whenever Nylea's Colossus or another enchantment enters the battlefield under your control, double target creature's power and toughness until end of turn.

Shadowheart, Dark Justiciar

{1}{B}, {T}, Sacrifice another creature: Draw X cards, where X is that creature's power.
Choose a Background (You can have a Background as a second commander.)

Broken Visage

Destroy target nonartifact attacking creature. It can't be regenerated. Create a black Spirit creature token. Its power is equal to that creature's power and its toughness is equal to that creature's toughness. Sacrifice the token at the beginning of the next end step.

Monstrous Onslaught

Monstrous Onslaught deals X damage divided as you choose among any number of target creatures, where X is the greatest power among creatures you control as you cast this spell.

Corpse Cobble

As an additional cost to cast this spell, sacrifice any number of creatures.
Create an X/X blue and black Zombie creature token with menace, where X is the total power of the sacrificed creatures.
Flashback {3}{U}{B} (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)

Oversimplify

Exile all creatures. Each player creates a 0/0 green and blue Fractal creature token and puts a number of +1/+1 counters on it equal to the total power of creatures they controlled that were exiled this way.

Disciple of Bolas

When Disciple of Bolas enters the battlefield, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.