Weapons
Weapon Lv. 1 - Every +1 upgrade gives 2 ATK, 0~3 ATK for every Over Upgrade pass the +7 safety limit, and ? ATK for every High Upgrade pass +15.
Weapon Lv. 2 - Every +1 upgrade gives 3 ATK, 0~5 ATK for every Over Upgrade pass the +6 safety limit, and ? ATK for every High Upgrade pass +15.
Weapon Lv. 3 - Every +1 upgrade gives 5 ATK, 0~8 ATK for every Over Upgrade pass the +5 safety limit, and ? ATK for every High Upgrade pass +15.
Weapon Lv. 4 - Every +1 upgrade gives 7 ATK, 0~14 ATK for every Over Upgrade pass the +4 safety limit, and 12 ATK for every High Upgrade pass +15.
A +20 level 4 weapon gives 201~424 extra ATK and MATK.
ATTN Everyone:
If you're going to grab info. from the iRO, please check if you're not in the Renewal Archives, you need to go to the PRE-RE so it can be more accuarate for our pre-Renewal server. It can be very misleading, pre-RE here:
Weapons
Weapon Lv. 1 - Every +1 upgrade gives +2 ATK (+3 ATK for every overupgrade).
Weapon Lv. 2 - Every +1 upgrade gives +3 ATK (+5 ATK for every overupgrade).
Weapon Lv. 3 - Every +1 upgrade gives +5 ATK (+7 ATK for every overupgrade).
Weapon Lv. 4 - Every +1 upgrade gives +7 ATK (+13(?) ATK for every overupgrade).
Armors
Every +1 upgrade gives +1 (it's actually only 0.66) Equipment DEF (not VIT DEF).