Choir of the Trench

At the beginning of each players endstep, put a
+1/+1 counter on Choir of the Trench. If you
control four or more other Leviathans, draw a
card.
Whenever Choir of the Trench attacks, mill
cards equal to it's power and create a 0/1 blue
Pod creature token that has "When this creature
dies, create a 3/3 blue Leviathan creature
token."