Quote Originally Posted by KittyPr View Post
we farmed during about 2hours and got 6 "tokens" !! (with 4 ppl )
Definitely go in with a full group. Find an area to farm in and pretty much kill anything your puller(s) bring. I'm actually unsure if it was even an hour now (maybe an hour and a half), but I eventually left Eureka with around 18-19 crystals and even gained a level.
Also make sure you're killing mobs your group pulls and not mobs that have already been claimed by others. Drop rate is lower.