haven't used rangers so far because they are pretty terrible atm , but i kinda doubt that. If you could place a trap on top of an enemy (let's say a mega golem just for argument's sake) , and stun it , then you could easily spam traps on top of it and keep it in place as long as you have traps.....which would be straight up OP. You could keep a megaboss ocupied like that for around 30 seconds without blocking it , which is why I seriously doubt that you could place traps on a slot occupied already.