Leveling up is vital to success in Persona 5 The Phantom X, as it unlocks new skills for your characters, increases your stats, and, in Wonder’s Case, unlocks additional Persona slots to utilize in combat. Leveling up your party members is relatively straightforward as long as you have enough Stamina, but earning EXP for Wonder works a little bit differently.
Leveling up Wonder in Persona 5 The Phantom X requires you to earn exp through the completion of main missions, side missions, Phantom Pass objectives, and Lufel’s Plan objectives. It can also be earned when completing certain difficult battles in Palaces and Mementos.

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How to Get Money Fast in Persona 5 Phantom X
This guide will help players get more money in Persona 5 The Phantom X. It includes every method to gain more money and how to claim money rewards.
How to Level Up The Protagonist Quickly in Persona 5 The Phantom X
Wonder gains experience from most actions you take while playing Persona 5 The Phantom X, which is helpful since Thief Compendium items can’t be used on him. Wonder will gain a decent amount of EXP whenever you complete a Main Mission or Side Mission, and smaller amounts whenever you complete a Phantom Pass objective or one of Lufel’s Plan objectives. Certain significant battles when exploring Palaces and Mementos will also provide Wonder EXP when completed. When completing challenges in the Realm of Repression, Wonder will also gain some EXP, and this EXP will be multiplied just like the rewards if you spend extra stamina when claiming rewards.
Early on, the best ways to increase Wonder’s level are by completing side missions and taking on Realm of Repression challenges. In the Realm of Repression, taking on Pursuit of Honor and Alluring Aroma Challenges is probably the most efficient method early on, since these will also provide you with the necessary items to level up and strengthen your other characters. Some early side missions that are particularly valuable for this include Capsule Machine Fun and Abnormal Surge, which unlock new game mechanics when completed. Hear the Cry of Muscles is also a good choice, as it unlocks a new city activity.
You can see all the available main and side missions in the mission menu, on Wonder’s Phone.
How to Level Up Party Members Quickly in Persona 5 The Phantom X
Party Members are a fair bit easier to level up when compared to Wonder, since you can use Thief Compendium items to immediately apply huge amounts of EXP to a party member of your choice. You can earn Thief Compendium Items in large quantities by completing Pursuit of Honor challenges in the Realm of Repression (accessed via the Mementos Menu). Higher levels of Pursuit of Honor will offer better rewards.
When a Party Member hits their current level cap, you’ll need to use Hidden Ability Materials to increase their level cap. These can be obtained from another set of challenges in the Realm of Repression, called “Alluring Aroma.” Many characters have abilities that increase in potency at certain level milestones, which are usually levels 50 and 70.
When taking on these challenges in the Realm of Repression, you must spend Stamina to claim your rewards. Stamina regenerates slowly over time and caps at 240, but after completing a challenge, you can spend extra Stamina to claim additional rewards as if you’d completed the challenge multiple times, up to a limit of 5 completions’ worth of rewards in exchange for 150 Stamina. By taking advantage of this, you can quickly amass huge amounts of Thief Compendium and Hidden Ability items to strengthen your party.