How the exploit works:
1.Have a Monk
2.Make party with the low lvl hero you want to lvl up
3.Let the low lvl hero stay in town
4.Get 5 NV on your monk
5.Start farming xp with the monk using Tempest Rush
6. Low lvl hero in town gets all the xp
P.s.
1.Items like cains set works
2. You also get all the massacre and stufff bonus xp