The last of the Calling Card riddles directs the party directly here. Once the party enters, King Leo announces that it is a trap and lights the building on fire, telling the party that fire traps will erupt on each floor after a certain amount of time, giving the party 10 minutes to escape from the burning building, with no enemies being encountered until the party reaches the 4th floor. A large group of children gets caught up on this due to being on a field trip to the museum, leaving the party to rescue them on their way to the roof; the party will not be allowed to advance until all the children on a floor are found. On the 2nd floor, Ixquic is found in a plane with the entire floor beneath on fire; Maya will offer to jump down to rescue Ixquic; allow her to do so to get her Prime Persona later. Once the party reaches the roof, they will be confronted by King Leo, where he blows up Smile Hirasaka and GOLD, if they weren't already destroyed, before falling through the roof of the museum. The party then escapes in the blimp attached to the building, however King Leo attacks them and lights the blimp on fire. The party defeats him and takes his Fire Crystal Skull, which is used to collect Ideal Energy, and then find out that rumors are now circulating labeling the party as the Masked Circle terrorists; the party uses the children to spread a counter-rumor to contradict this, which creates problems later on.
The team first enters the Sky Museum in order to find Tatsuya Sudou. There, they find kids from a school in a field trip, and Jun Kashihara; Both he and Maya have the impression that they've met before. Jun then explains that he went to the museum as a letter told him to, in order to meet a "friend." Afterwards, Sudou's voice appears from a speaker and says that several bombs are timed to go off in 30 minutes, "just like in the Other Side" as he puts it. From this moment on, the party has 30 minutes to find all the children in all the floors, and take them to the roof. Time passes during battles as well, and even while the menu and map are open. Upon reaching 4F, Sudou makes it clear that he's just trying to remake the happenings of the Other Side, in order to make Maya remember.
On the rooftop, the team meets Sudou, which has taken Jun as hostage, and the "Deja Vu Boy" (Tatsuya Suou). The remaining bombs then explode, creating a hole on the floor, which Jun pushes Sudou into after the latter attempts to kill Maya. The team, plus Tatsuya and Jun, then enter the blimp located in the rooftop, and fly away as the museum explodes. However, Sudou manages to get into the blimp, and a boss battle ensues. Tatsuya briefly joins the party at this point for the battle.
Once the battle is over, Sudou dies, and the blimp crashes. Tatsuya is not seen on the shore the team and Jun appear on.
- 2F: Dx Card x1, Revival Bead x2
- 3F: True Force x1, Lu Incense x1
- 4F: Miracle Egg x1
- 2F: Item/Medicine (x3), Item/Ball of Returning (x2)
- 3F: Item/Bead of Protection, Item/Damascus Drink, Item/Gala-Gala Drink (x2)
- 4F: Item/Incense of Life, Item/Chewing Soul (x2)
- Indigo boxes indicate Innocent Sin bosses.
- Purple boxes indicate Eternal Punishment Bosses.
|Leo Mask 2||22||154||Leo||-||-||-||-||-||Rp||Wk||-||-||-||-||-||St||St||-||St||Agilao Card||-|
|Kabandha||25||208||Hanged Man||-||-||-||-||-||Wk||Nu||-||-||-||-||-||St||St||-||St||Magical Guard||Magic Mirror Card|
|Pyro Jack||26||190||Lovers||-||-||-||-||-||Dr||Wk||-||-||-||-||-||St||St||-||St||Agi Card||Agilao Card|
|Taranis||27||228||Chariot||St||St||St||St||St||Wk||Wk||Wk||Wk||Wk||Wk||Wk||-||-||Wk||-||Silver Manisha||Garula Card|
|Kanaloa||27||230||Tower||-||-||-||-||-||-||Nu||-||-||-||-||-||Nu||Nu||-||St||Dia Card||Diarama Card|
|King Leo||29||2067||?||-||-||-||-||-||Rp||Wk||-||-||Wk||-||Rp||St||Nu||-||Nu||Fire Crystal Skull||-|
|Cockatrice||11||81||World||Shot, Earth||Sword, Attack||-||-||-||4F|
|Moh Shuvuu||12||88||Temperance||Shot, Earth||Sword, Attack||-||-||-||4F|
|Shax||12||350||?||Shot, Fire, Earth||Sword, Attack||Water||-||-||Blimp|
- Treasure and enemy info for Eternal Punishment from FAQ/Walkthrough by Yushiro