Siege Wurm

This creature can't be blocked. When this creature enters, return a creature you control to its owner's hand.

Flying Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

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.) Choose one — • Create a 2/2 green and white Elf Knight creature token with vigilance. • Destroy target artifact or enchantment.

Target creature you don't control gets -4/-0 until end of turn. Overload 2U (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Afterlife 2 (When this creature dies, create two 1/1 white and black Spirit creature tokens with flying.)

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.) Flying

(T: Add W or B.) As this land enters, you may pay 2 life. If you don't, it enters tapped.

Whenever a creature you control attacks alone, it gets +X/+X until end of turn, where X is the number of creatures you control.