"Those are just pebbles," Nick couldn't understand why these pebbles were important.
But what he could see was that Peter was dumping them all in the barrier and googling like mad.
Nick decided that Peter was simply highly homicidal and that Peter could one day get them all into trouble.
"Oh don't you worry, this is breakfast, lunch, and dinner!" Peter said, knowing that what he said was not actually logical. "How was I supposed to get so many pebbles otherwise?"
Peter dumped another bucket full of pebbles in the watery.goo that was left of the goblin village.
"Yes but why were the pebbles inside of the watchtower?" Nick had a very bad feeling about it all. Knowing Peter, those pebbles could be gravestones or maybe something to note the passage of time or well...
Nick didn't know much about goblins, but he was pretty sure that those pebbles were probably going to cause them a lot.