The Witcher 3: Wild Hunt GAME MOD Slots ...
For The Witcher 3: Wild Hunt on the PlayStation 4, a GameFAQs message board topic titled "Skill points needed to unlock the 4 extra ability slots?".
How To Get More Ability Slots With Mutations In The Witcher 3
The following guide will tell you how to get more ability slots using Mutagens for Geralt in The Witcher 3: Wild Hunt.
Upgrades | The Witcher 3 Wiki
The Witcher 3: Wild Hunt horse guide tells you all you need to know about your mount, and where to find and buy upgrades for inventory slots.