Diablo III: Reaper of Souls

Yep just around 2 hours. Had 2 friends run me through T6, which was netting me a level every 1-2 mobs in the lower levels in Act I from the very start.

Oh, well that doesn't exactly count as a viable method then. As much as I want to get the achievements, I can't really drag SP people along repeatedly to help cap my characters.

In the meantime just to let people know, with my Paragon 32, Cain's Set, and a Ruby, I've able to get a level 60 in ~12 hours. Not the fastest, but still better than before where it must've been ~40~60 hours. Not sure how fast everyone else here is capping any alts during this Community Buff event.