I know I can upgrade runes by cubing 2xsame runes > rune 1lvl higher. But I want to know if I can downgrade runes. If not, whats the best way to farm low level runes? I need a bunch of NEFs for my build...
Early on, if you need guaranteed low rune, you can farm countess and open chests. However, as soon as you can craft jewels you can easily make something better than nef.