a lot of players come back to diablo 3 to prepare for the reaper of souls after a long time away from keyboard. and let me tell you as a player who stick to the player always that decaying crypt is the hot spot for fast power leveling especially barbarian right now. two-handed skorn ww rend build would be the perfect build to do this run. if you still have the skorn in stock, it save you a lot of time. otherwise, it is cheap to buy a skorn with life steal stats in the auction house.
ww rend barbarian decaying crypt videos:
ww rend barbarian skills and runes: http://us.battle.net/d3/en/calculator/barbarian#chrkpu!gzh!azyccz
choose passive skill unforgiving first to prepare your fury to full amount. then battle rage to increase critical hit chance. then change unforgiving to weapons master. if you use skorn, you would get 10% critical hit chance. as we suggest skorn with life steal and immortal king belt to get around 5% life steal, we would not use passive skill bloodthirst. instead, we would use brawler to increase your damage by 30% if there are 3 monsters within 8 yeards. brawler is a great skill for you except in the uber boss fight.
items requirements in mp10:
50k ehp
500 all resistance
150k dps unbuff
5% life steal
if you have low dps, you life steal would not work properly. you can do the math. 150k dps with full buffs, you can do as high as 280k damage and get around 1.4k life per hit. but to a 50k ehp barbarian, it is not much. if you want to farm efficiently on mp10, you should try 150k dps at least. to meet the ehp and resistance standards, you can consider the use of shield with strength, vitality, all resistance, critical hit chance.