The dog has learned to knock over piles.
The owner taught his dog to knock over shot glasses as deftly as bar patrons do.
Dogs are very intelligent creatures, and therefore they are excellent at remembering and following many different commands. Some teams invented by doggie owners are particularly creative. For example, the owner of the furry hero of this video taught him how to knock back shots.
The dog began to knock over the glasses as deftly as a typical bar patron. It’s good that the person didn’t fill them with anything. Otherwise, the dog would instantly fall off after the first glass. After all, alcohol, especially strong alcohol, can be very dangerous for pets.