>>6032487I think I understand why they put this jokester in the wave now. They wanted to give people an easy way to gather asylum outfits so Batman can capture the obscure villains, but they didn't want to prevent a D-lister from wearing their iconic costume.
Since Joker is a must in this series, they decided to just make him the one with the Arkham wear. This way they kill two birds with one stone without compromising another spot for an additional Joker minifig.
