Forgotten Tales

I was slowing a couple guys with a slow spell when....
They,suddenly unslowed(obviously unfreeze pot but) When they did
They gained 75%+ speed. Much faster then normal walking speed. You would think they used a speed pot but they were archers and mages. Is this a bug? If so I got info for it idk if I am missing something or not

Yeah happened to me too. I didn't slowed someone. but someone slowed me. and with my mage I unfrezzed and gained alots of speed.for some time,.

I've tried to reproduce this and succeeded once out of couple dozen tries. I can not understand the exact circumstances for this to happen, looked random to me.
So, if you ever figure out how to reproduce this with some more certainty than 'it does happen sometimes', please tell us.