The skills from [Bringer of All], that is, those processed from the skill(s) that Replicus inputted into the skill in addition to the Apostles he wanted to merge with, were forcefully emboldened from the rank of their source.
For instance, back in Inhone City, Skullius had used [Bringer of All] in conjunction with [Mana Force] to obtain a bunch of new mana-related skills. They had all been very efficient against the threat at the time, the Galemonger, because they had been elevated generously by means that didn't conform to the logic of Normal, Special, Super or Supreme.
(A/N: Refer to Ch.332.).
These skills were simply better than the original, and where Null Life was involved, Replicus could safely say this wasn't the first time he noticed his prowess breaking Aigas' power system modestly.
All this was to say [Bringer of All] was a cheat Class skill that allowed its user to gain and use skills several levels above what they should have.