Henika, Grand Mage

Whenever you cast a elf create a x/x elf creature
token where x is half the amount of elves you control rounded up
{4}{g}{g}: Henika, Grand Mage gets trample and
+x/+x where x is half of the number of elves you control rounded up
When a player takes 17 commander damage from Henika, Grand Mage they lose the game