In a way, it requires hongmoon dragon soups.
Wich gives you 100% xp for killed enemies.
So at certain levels, you just farm certain dungeons/areas solo.
Still takes time, but goes faster for sure.
You can do 1-45 in 14-15hours if you play hardcore

Without doing that, you can totally hit 45 in 2 days without a problem if you go ham.
This post was edited by Sphynxi on Feb 8 2016 05:19pm