What kind of ability would acquiring new attacks mid-fight fall into?

[TartaChocholate]

A character can obtain new moves as he fights and suddenly improve versions of already existing attacks as the battle continues, but once the fight is done and he "cools down" those attacks won't be available again until he reacquires them in another fight.

Seems a bit obtuse but in exectution is actually quite simple. At first I thought it would be something akin to a Lesser version of Accelerated Development, specifically the Abilities variant. But want to make sure.

Thanks in advance!