Did you hit someone that had void shield? void shield has a chance to remove buffs from the enemy team... Yeah, they are pretty good.
If thorns or other talismans existed this Prisoner thing would be solved. He can't disable talisman passives, can he? I never had a chance to test. What if you reintroduce thorns and other kinds of talismans, or even change some like blizzard shield to give a passive shield much like repel does, that affects all team and then one every round...