Sub-abilities is mastery type thing but, instead of the simple old quest reward and the mastery being mostly better, it (referring as sub-abilities) can be worse and having a new gimmick, they could/should be obtained by having more punches than the ability itself (it works like mastery as a toggle) or a task like mastery but easier to obtain or have badges from other games.
EXAPLE: 1
bone is similar to sans abilities right, add a sub-ability of bone which will have sans blaster and stuff (im not writing its abilities cuz this is for sub-abilities), 2 buff would have a strong punch and a smash as a sub-ability
Notes: Sub-ability's main purpose is for adding the more ability/gimmick which didnt exist before in mastery/normal version
It can be worse it can be better, and it should be toggle from the npc where u toggle masteries
Seasonal Abilities you guys can add sub-abilities for seasonal abilities for more content and stuff
Thank you for ready bye 🙂