Persona 5 introduces Mementos Dungeon, Persona Fusion

Send off your Persona for training.

The latest issue of Weekly Famitsu offers new details on Persona 5‘s Mementos Dungeon and Personas.

Here’s the information:

Mementos Dungeon
Different from the Palace, which are dungeons created as reflections of the hearts of the general public, the Mementos Dungeon is a random dungeon whose form changes each time you enter. There are quests to find and reform the Shadows lurking within, but since Shadows are based on the general public, their trends of action will change according to things such as the day’s weather.
If you missed it, catch the Mementos Dungeon in action here.
Personas

Your Personas will gain experience point bonuses depending on your level with Cooperation Characters. And the more skills a Persona has acquired, the more skills that can be carried over during Persona fusion. You can select which skills are carried over if you want, too.
Guillotine (Persona Fusion)
In Persona 5, Persona fusion is carried out at the Guillotine. There’s the “Two-Body Guillotine,” “Group Guillotine,” and “Search Guillotine.” The last one perhaps lets you summon a specified Persona from a book of illustrations, even without a guillotine.
Hanging – Sacrifice one Persona as experience points for another Persona. There are social game training-like elements to it. If the Personas are of the same Arcana, the experience points you acquire will increase.
Electric Chair – Sacrifice a Persona to create a high-rank item or tool.
Solitary Send-Off – Send off and your Persona to train and learn skills to overcome their weaknesses. The required number of in-game days is shortened based on your Arcana Co-op Level.
According to Persona 5 director Katsura Hashino, the reason that these all sound like executions is to keep in line with the game’s theme of erasing your own mask and giving birth to a new self.