Currently Emerald Ring is giving +100% bonus (or so) to the Arrow storm skill.
Tested on the test server:
No Emerald Rings:
1 Emerald Ring:
2 Emerald Rings:
As we can see, each subsequent ER increases AS damage by roughly 100%. Additional testing showed that it might be not just AS:
No ER, normal atk:
1 ER Normal Atk:
2 ER normal atk:
As we can see, each ER adds +100% normal attack as well.
My hunch is it currently adds +100% ranged damage, that might explain AS damage. It shouldn't Nothing in the script indicates that.
On double strife LV 10, each ER gives +10 dex, +10 agi + 10 vit and +100 atk.
Currently +100 atk bonus is NOT added
As we can see it only adds StatusATK due to increase in Dex.
So currently ER gives improper bonuses to atk (it ONLY should affect arrow shower, double strife and Severe Rainstorm, nothing else)
And doesn't give +20 atk/2 levels double strife.