Karuuk, The Zombie Leader

When Karuuk, The Zombie Leader enters the battlefield create a 2/2 Zombie creature token
Zombies you control have menace
{b}{b}{t} Create a 2/2 zombie creature token
Whenever you cast a zombie from your hand you
may pay {4}{b}{b}{b}. If you do, put a +1/+1
counter on all zombies you control.