My guess is you are fighting things with alot more def/physical resistance is why slug is doing poor. Which from what I gather is most VW nms. Also lvl correct always hurts melee more than magic. Given your stats assuming no physical resistance and at proper distance you'd have to have a pdif down around 1ish to get the dmg you had. Which is really low considering how much ratt a rng gets. Though being out of the sweet spot cuts it alot. Comparatively older nms like saremeya or kirin I could do 2.5k at 85 with WoE gun.
Also yes not being in sweet spot will make a huge difference and maybe some ratt food. And well look at your slug gear. You have tons and tons of racc in it. Very very little stat boost, str or ratt. Not sure how much you need but that does seem a bit much
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