Common (red) voucher

Hi, where can i farm fast common (red) voucher, was common df long time ago, i forgot where have good drop. I need best way for legit farm. xD
Atm lv 57, i test crespo, parca but sucks drop.

Castor 2, Narok (or Narak, i cant remember) 2, then crespo, i think its the best in N2 couse there arent alot of bots there.