I'm not sure which still you mean, but you could check Brad's skill tree, and the laboratory for optional skills.
The only other ways to get skills are events or with equipment. I don't recall such a skill on a weapon, but maybe I just forgot about it.
Else, if that was a long time ago, there is also that option that the skill was changed or removed at some point during the development.
Version 24.08.09 brother
It is just brad making normal 3 attack randomly
Like first attack randomly on target 1 or 2 or 3
Second attack randomly on target 1 or 2 or 3
Third attack randomly on target 1 or 2 or 3
TP cost is around 10 to 15.
I don't know where I get it either.may be I get it from events or may be it is from level 99 break to 100 and give new skills on characters.if brother cannot remember that,it is ok.I will explore more.
I am your big fun brother.
I like your game development.thank you brother....
I am waiting for news ....