It looks like some people here are still having trouble understanding how Warlock's abilities work.
A warlock does not need intelligence or wisdom, learning or magical books and scrolls.
His power comes from himself.
Mages tap into an external source of power, but in the case of a warlock, that source is himself.
Warlock a little similar to the sorcerers, but much more similar to dragons, demons and all outsiders.
Their magic is innate and they all use charisma as their casting stat.
In order for a Warlock to use his powers, his patron must fundamentally change him.
It is not something that can be reversed.
It's kind of like a demon lord power-pumping his favorite demon to transform it into a higher-level demon.
Warlock was also transformed.
