Yeah that Fit Puzzle Block style mini-game. I will say it gets annoying later on because you have to use the higher rarity ones and they take up more space with more weird parts cut out but if you manage to do it it really feels rewarding. Getting that Expert Level +15 is incredible.

I think it's just the easiest spot to set it up. We get some Commissions there too and I think another event also used the space.