Please remember that as per the game’s ToS, stripping down in Colosseum or Duels so that your friends can hit you and get free points every time you reach a safety rank, is not fair play and is against the spirit of the game, so it can get both attacker and attacked person banned. We do not refer to legitimate Colosseum/Duel hits, but mostly to cases where a player removes gear and team members or even refills health so their guild or friends can hit them to get points for free.
ToS post about it is here