Ilysian Caryatid

{T}: Add one mana of any color. If you control a creature with power 4 or greater, add two mana of any one color instead.

Drowsing Tyrannodon

Defender (This creature can't attack.)
As long as you control a creature with power 4 or greater, Drowsing Tyrannodon can attack as though it didn't have defender.

Challenger Troll

Each creature you control with power 4 or greater can't be blocked by more than one creature.

Thriving Grove

Thriving Grove enters tapped. As it enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Forest

Bristling Boar

Bristling Boar can't be blocked by more than one creature.

Ornery Dilophosaur

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever Ornery Dilophosaur attacks, if you control a creature with power 4 or greater, Ornery Dilophosaur gets +2/+2 until end of turn.

Giant Ladybug

Reach
When Giant Ladybug enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

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.

Spectral Hunt-Caller

{5}{G}: Creatures you control get +1/+1 and gain trample until end of turn.

Hammer of Ruin

Equipped creature gets +2/+0.
Whenever equipped creature deals combat damage to a player, you may destroy target Equipment that player controls.
Equip {2}

Prowling Serpopard

This spell can't be countered.
Creature spells you control can't be countered.

Colossal Majesty

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

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.