Just a note for people trying to do this:
Get a team of 3-5 and go into play vs AI on beginner mode. Follow the objective of each map if it has one to win. If it's just a "destroy the nexus" take your team and just push one lane. It'll take you an average of 5-7 mins to win if you're not terrible.
Try not to die, if you're very low life and have no way to heal press "b" (default key) to go back to your "Hearthstone" (home base) to heal quickly.
If you don't die the matches go by very quickly.
Took us a little under 2 hours to do all 15 matches.
This post was edited by cejss on Nov 16 2016 05:23pm