One barrel went careening off of the side of Neighagra Falls. Inside it was a shrieking Sombra.
Next went Tirek, who had been shrunken by Discord even further to mess with him. He tumbled within a plastic toy barrel meant for the monkey-in-a-barrel line of foal's toys. Complete with monkeys.
After that the Storm King's petrified body was bucked straight off of the top of the falls at full-force.
Queen Chrysalis was thrown overboard next, screaming curses and bloody murder towards the changelings that betrayed her as she fell towards the bottom.
Finally, a large pile of pies in a barrel was dumped via wheelbarrow. Because Rainbow doesn't like pies.