Endless Maws

When Endless Maws enters the battlefield and whenever a Maw you control dies, put a +1/+1 counter on Endless Maws.
At the beginning of your end step, if you control less Maw creature tokens than the
number of +1/+1 counters on Endless Maws, create a number of 1/1 blue and green Maw creature tokens equal to the difference.