I have been performing against Bremen for the past couple of days without any shards dropping for the heroes. I'm level 265 against Bremen (second tier) but because I hadn't finished collecting the first-tier heroes, I went back to those (Bremen capped at level 210). I first finished getting all the shards for Bremen's second-tier hero and then went back to the first tier to try to finish getting the two heroes from that tier I don't already have.
I've probably attacked first-tier Bremen 60+ times over the past day and a half or so without a single shard dropping, so wanted to check whether this was a quirk of how I've approached collecting Bremen's heroes (i.e., collecting the second-tier hero before going back to collecting the first, which has confused the algorithm that drops shards during performances) or whether I have just been _really_ unlucky.
Could you investigate, please?
Cheers.