That's according to Bandai Namco.

The Lair of the Lost Lord features new backstories for Tani and Bracken, new magical Nazacaän weapons, and new gameplay elements to Ni no Kuni II: REVENANT KINGDOM.

The first is a new gameplay addition is a labyrinth dungeon where the lost lord is said to reside. This dungeon randomly generated levels of increasing difficulty and new dangers to tackle as Evan and his friends travel deeper into the lair to discover its secrets. Players will be able to access the new dungeon starting in the fourth chapter of the game.

The other gameplay addition is the ability to switch out each character’s fighting style using the Method System. After obtaining these Methods a new battle type will be selectable from the menu screen. Master these new Methods to bring down tough enemies.

I'm not 100% sure I'll have time to play this this week but I had a pleasant enough time with NNK2 that I'll probably try to tackle it at some point. Weird to release it on a Thursday, though. Maybe we'll take a look on UPF or something.