I wouldn't call this an exploit, but here it goes. Around a week ago, a known Youtuber named Rhykker posted a video explaining an exploit on Act 3 on adventure mode where you talked to a guy that was hurt and bring the news up to another guy, doing this on torment 6 gave you around 12M exp.
Now someone found a so called "exploit" which is based on the same idea, but this one has 0 mobs.
If you do this with a friend, your friend can stay down by the other guy, while you go up and talk to the vendor/merchant. This way you do not need to go back down.