Not a pentakill, but one of my daily quests has get 3 double kills, now I am sure that for someone that PvP’s a lot that is extremely easy, as someone who mostly solo que’s and doesn’t really like PvP I can look at my stats and see: 80 Matches played, and 27 double kills, or about 1 double kill for every 3 games played. And I am pretty sure that most of those were from bot matches (didn’t think to check before the bot matches).
So I am looking at at least 9 PvP matches, which on PC including que time I would figure to be at least 6 solid hours of playing a mode I don’t like. However, like I said the vast majority of those probably were bot matches, and I would figure it would be close to 10 matches to get a double kill on average, which would bring me to 30 games played or about 20 hours of a mode I don’t like…to get 10 platinum, and if it doesn’t fall of the daily quest list it’s just a matter of time until I don’t have a daily quest list anymore because it’s just filled with quests that I won’t do.