Keyword: Ferocious

Target creature gains double strike until end of turn. (It deals both first-strike and regular combat damage.)
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

: Add .
Ferocious — : Add . Activate this ability only if you control a creature with power 4 or greater.

Flying, haste
Flamewake Phoenix attacks each combat if able.
Ferocious — At the beginning of combat on your turn, if you control a creature with power 4 or greater, you may pay . If you do, return Flamewake Phoenix from your graveyard to the battlefield.

Tap X target creatures.
Ferocious — If you control a creature with power 4 or greater, those creatures don’t untap during their controllers’ next untap steps.

Deathtouch
Ferocious — Whenever Heir of the Wilds attacks, if you control a creature with power 4 or greater, Heir of the Wilds gets +1/+1 until end of turn.

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.

Barrage of Boulders deals 1 damage to each creature you don’t control.
Ferocious — If you control a creature with power 4 or greater, creatures can’t block this turn.

Reveal the top eight cards of your library. You may put a creature card from among them onto the battlefield. Put the rest into your graveyard.
Ferocious — If you control a creature with power 4 or greater, you may put two creature cards onto the battlefield instead of one.

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.

Return target creature to its owner’s hand.
Ferocious — If you control a creature with power 4 or greater, you may draw a card. If you do, discard a card.

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.

Counter target noncreature spell unless its controller pays .
Ferocious — If you control a creature with power 4 or greater, counter that spell instead.

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.

You gain 5 life.
Ferocious — You gain 10 life instead if you control a creature with power 4 or greater.

Ferocious — If you control a creature with power 4 or greater, you may cast Dragon Grip as though it had flash. (You may cast it any time you could cast an instant.)
Enchant creature
Enchanted creature gets +2/+0 and has first strike.

Tap X target creatures.
Ferocious — If you control a creature with power 4 or greater, those creatures don’t untap during their controllers’ next untap steps.

Deathtouch
Ferocious — Whenever Heir of the Wilds attacks, if you control a creature with power 4 or greater, Heir of the Wilds gets +1/+1 until end of turn.