triceratops herd

when triceratops enters the battlefield
create six 6/6 triceratops creature tokens
with trample and one 1/1 baby triceratops creature token
At the beginning of your upkeep, put a
+1/+1 counter on Baby Triceratops. When Baby Triceratops reaches 6/6 replace Baby Triceratops with a 6/6 Triceratops creature token with Trample.