If you use 1 hero (3 better) SSS rank, in the open world (Sakura, etc.) I think it's okay. But for events, it's not recommended to use x999 dmg/deff. You can look for safe under x100 (but it's safer under x60, for example x35, etc.) dmg/deff. how about CD skills? Don't do it too often, because sometimes it bugs. the point is don't overdo it okay