How you know, a full party of 9 players gives a EXP bonus. But fact is, not just full parties gives EXP bonus. A full party just gives the most bonus.

- it only works when all in the party grinds like hell - its a rare thing because people feel confortable in shared party and used to get lazy...
- the level range of the party is low, and noone is hitting mobs that are blue to any other member of the party. So the maximum range of the "good" shared party can be 5, if we'r assuming that the lowest member will grind on "high yellow" mobs.

Heres the calculation tables that shows the result of the GC1 test:



How you see, not just full parties give EXP bonus.
I hope, this will help you on grinding and level up.

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