Other people have reported this already but figured I'd add a bit more.
For some reason bosses in the Battlesphere load in different bosses when hitting the Retry button after a win, this seems to default to certain bosses on a specific range. From what i can gather, Proto Pincer up to BFF-2000 load in the Lancer fight. Duality up to Titan Armor 2.0 load in Bakunawa Rush's boss. And Merga Bloodmoon up to the secret boss trigger Blue Moon
#Battlesphere bosses retry option
harsh pumice
haven't tried out all bosses but that seems to be the case, not sure if it would happen when you haven't unlocked said bosses
figured i'd get these 2 to show examples
although, it seems the Titan Armor 1 with the BFF-2000 doesn' trigger this effect, that one does load in normally when hitting the retry button, thought that was funny
pastel burrow
I'm bumping it because the same issue happens in the Training Dojo sparring. After restarting fight with any character, it will always load fight with Gong (the challenge ID gets set to 0, which might explain it)
crimson canopy
I’m willing to bet this seemingly random bug was due to the Newley announced boss rush mode
remote pumice
No it's actually completely unrelated lol