Reverse 1999 Mane’s Bulletin Joint Reports is a new Version 3.9 activity where you fight three bosses and combine their damage scores for rewards. Before each investigation, you may add up to four assisting characters whose combinations activate Cooperation Skills. Each assistant can help in only one investigation, so don’t assign all your best options to the first boss without considering the other two.
The mode is part of Mane’s Bulletin: Featured Observations, which began after the 5 November update and runs until 17 December 2026 at 09:59 GMT. Complete main story 1ST-16 Heaven Apostles first. Here’s the three-boss scoring system, how assistants work and what to do if your combined score isn’t enough for the next reward.
How to enter Reverse 1999 Mane’s Bulletin Joint Reports
Open Mane’s Bulletin and find Featured Observations once the main story prerequisite is met. Select Joint Reports rather than Regular Reports. Both modes received a new Assist feature, but the three-boss total and the restriction on using each assistant only once are specific to the Joint Reports setup.
The current event’s server end is 17 December at 04:59 (UTC-5), equivalent to 09:59 GMT, 10:59 CET and 18:59 JST. Make sure you’ve collected any completed score rewards before that deadline. The published notice doesn’t name a separate extra claim period.
Reverse 1999 Mane’s Bulletin Joint Reports: scoring across three bosses
Fight all three bosses and deal as much damage as your teams can manage. The score from each fight is added to produce a combined total. That total is what you compare with the reward milestones. Even a modest score in your weakest investigation can move you to the next threshold.
Look at the actual boss information before choosing teams. The release notice doesn’t include every boss weakness, cooperation-skill formula or reward number for Version 3.9, so specific tier recommendations need the live battle menu. Avoid copying team advice from an earlier Mane’s Bulletin rotation without checking it still applies.
How to assign assistants for Reverse 1999 Mane’s Bulletin Joint Reports
You can select as many as four assisting Arcanists before an individual boss fight. Certain combinations unlock Cooperation Skills that buff the combat team. Check the combination effects on the selection screen, then spread your best synergies across the three investigations rather than assuming one assistant can be reused.
One assisting character may participate in one investigation only. Plan the first boss with the other two in mind, particularly if you have few developed characters. This doesn’t mean you need twelve specific six-stars or that assistant characters replace the primary combat lineup. The announcement confirms the assist allocation, not an exact must-have character list.
Joint Reports versus Regular Reports and Focused Flashback
Regular Reports uses the new general Assist feature too, but Reverse 1999 Mane’s Bulletin Joint Reports adds the three investigations, the four-assistant selection and their one-use assignment. Don’t assume Regular Reports follows exactly the same scoring and allocation. Focused Flashback is another separate mode: it uses multiple teams and round-limited stages to collect stars, rather than adding up boss-damage scores.
For Joint Reports, revisit the lowest-scoring boss first. If you can improve its assist combination or spread out a useful support, you may earn more combined points than by replaying a boss you’ve already handled comfortably. Compare the score and reward tabs after each attempt so you know what remains to claim.
When does Reverse 1999 Mane’s Bulletin Joint Reports end?
The Version 3.9 investigation period ends on 17 December at 09:59 GMT. Complete all three fights and claim the available milestones before then. Bluepoch doesn’t publish a universal highest-scoring party in the release summary, so the safest approach is to read each boss’s current vulnerabilities and its Cooperation Skill descriptions before spending your limited assists.
If you’re also following Rekindled: Games of the Summer-Gold Sea or Musae’s Arcade, keep their tasks separate. Neither uses the same three-investigation scoring system as Reverse 1999 Mane’s Bulletin Joint Reports.
Official source: Bluepoch’s Mane’s Bulletin Version 3.9 announcement.
