WarpMyMind

My useless sub has listened to several files and to no avail. looking for a file for it that is at the strongest strength to break it

hypnosis is closer to coercion that breaking. there is no "strongers file", as different people respond to hypnosis in their own ways. typically if someone is having trouble "getting files to work", its because they have their own myths about what hypnosis is and is not, and they end up giving themselves suggestions that the files are not working.

It also maybe the files you are using are the wrong type of suggestibility. Some respond better to visualization, others to sound, others to feelings, others to indirect orders and others to direct.. some do better with metaphorical stories,,,

Sometimes you need a different induction style...
But it is possible the files you are trying are against your subs core values too...

One of the major causes of lack of effect is trying to do too much, too soon. I would reccomend stepping back to having your sub try simple trance trainers like Bubble, Blink, orFailing to Resist once your sub learns to trance, THEN do submission files, starting with easy ones like Submission Trigger before moving on to more extreme files.