Enchantment

When Arboreal Alliance enters the battlefield, create an X/X green Treefolk creature token.
Whenever you attack with one or more Elves, populate. (Create a token that's a copy of a creature token you control.)

"First name the four, the free peoples:
Eldest of all, the elf-children . . ."
—*Long List of the Ents*

Artist(s): Alexander Mokhov