What are you playing?

To be fair, by the time you've unlocked the ability to replay all the days, if you've been stat grinding properly, it's not that hard to do the entire game on ultimate level 1, barring some of the last bosses. Especially the secret boss. Ugh.

...
True Fact:I never knew there was a secret boss.
...And I thought the Time Attack was brutal.
Overall, this is like playing Dream Drop Distance on Critical...but my god, I've had this game for ages and never knew about a secret boss?!
I. Am. Sad.