Moj mistrz said:
You cannot move barrels to prevent trap players.
I dont know if that was already reported, but if your pokemon is on you and you use harden move, then u will have harden animation and (not confirmed) 50% less damage takin' on you for several seconds.
Then to prevent trap players, a good idea would be that players could go on barrels, because you can make (with a bit of skills) that your poke moves the barrels as you wish, and you can also trap players or block ways, in my case barrels were blocking the way to go upstairs.
edit1: How to move barrels with your pokemon: Order your pokemon to go close to the barrel. After that, if barrel is between your pokemon and you, and for example charizard is on the left, the barrel is in the middle, and you're on the right, move your character to the right and charizard will move the barrel to the right.
edit2 and 3: mistakes of grammar corrected