Shaco Ult Can Grant Double Kill... GAMEPLAY

Ok, so I was in the top lane ganking a Nunu playing as the champion of Shaco. I popped my ulti, Nunu popped his. I killed Nunu at the same time he killed me, but my kill on Nunu was registered as a double kill, though the only person I had killed was Nunu. It may not be my job to theorycraft, but I believe this is due to my champion and my clone last hitting Nunu at the same time. Thus, registering two kills instead of one. Thanks.

THIS BUG ONLY APPEARS TO HAPPEN WHILE NUNU & SHACO BOTH HAVE THEIR ULTS AT THE SAME TIME AND KILL EACHOTHER. BETTER THREAD TO CLARIFY THIS BUG: http://forums.euw.leagueoflegends.com/board/showthread.php?t=1317854