Archangel of Strife

Flying
As this creature enters, each player chooses war or peace.
Creatures controlled by players who chose war get +3/+0.
Creatures controlled by players who chose peace get +0/+3.

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. ({G/P} can be paid with either {G} or 2 life.)

Tifa's Limit Break

Tiered (Choose one additional cost.)
• Somersault — {0} — Target creature gets +2/+2 until end of turn.
• Meteor Strikes — {2} — Double target creature's power and toughness until end of turn.
• Final Heaven — {6}{G} — Triple target creature's power and toughness until end of turn.

Mightform Harmonizer

Landfall — Whenever a land you control enters, double the power of target creature you control until end of turn.
Warp {2}{G} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

God-Eternal Rhonas

Deathtouch
When God-Eternal Rhonas enters, 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.

The Skullspore Nexus

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
Whenever one or more nontoken creatures you control die, create a green Fungus Dinosaur creature token with base power and toughness each equal to the total power of those creatures.
{2}, {T}: Double target creature's power 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.

Sister Repentia

Martyrdom — When this creature dies, you gain 2 life and draw two cards.
Miracle {W}{B} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Leonardo, Sewer Samurai

Sneak {2}{W}{W}
Double strike
During your turn, you may cast creature spells with power or toughness 1 or less from your graveyard. If you cast a spell this way, that creature enters with a finality counter on it. (If a creature with a finality counter on it would die, exile it instead.)

Doran, Besieged by Time

Each creature spell you cast with toughness greater than its power costs {1} less to cast.
Whenever a creature you control attacks or blocks, it gets +X/+X until end of turn, where X is the difference between its power and toughness.

Vindictive Lich

When this creature dies, choose one or more. Each mode must target a different player.
• Target opponent sacrifices a creature of their choice.
• Target opponent discards two cards.
• Target opponent loses 5 life.

Insatiable Souleater

{G/P}: This creature gains trample until end of turn. ({G/P} can be paid with either {G} or 2 life.)