You can kill the Dummys?

Okay im no pro at this game but i was testing out kayn in the Practise Tool and i saw goofing around and attacking the dummys until i suddenly aw first blood. I wondered who i killed and then i saw the dummy was gone so i attacked a few more dummies and managed to kill them all with ignite. I tried with other champs and it worked im not sure if this is meant to happen if someone could respond that would be nice!