So playing as Baron Blade in part 2, placing his turrets and Blade Battalions, what happens when they are defeated?
Do they go in a discard pile and when you run out are you out or do they go back to your hand so you never run out?
i ran out of battalions and auto turrets before the game ended
When they get destroyed they go back into your stock pile to be redeployed as you see fit
Redeployed in the normal manners, of course. Not just for free. (For clarity.)
Yeah, Foote gets a little crazy with turrets.
Fixed that for you. 
*Flips the table*
Thats what I think of your turrets! Now NONE of them make range!