Quote Originally Posted by Destrica View Post
Regarding the +s, for some reason I thought there was a way to increase it for the Phantom/Soul Weapons, but I guess that's not the case by the looks of it. Oh well...
Just wanted to make sure you knew that if you fodder +s into another weapon, it'll be added to the +s of that weapon. So if you fodder a +1 R you got from gemcha into your phantom/soul/whatever weapon that is +2, your phantom/soul/whatever will become +3 afterwards. The max is +99.

As for Erebus that does sound rather good, so long as the other team members cover the essentials already. The Kamihime wiki doesn't seem to have %s on the Vigor buff unfortunately.
20% according to the JP wiki if you have her leveled.