Experience

Experience, or exp, is what determines a Pokémon's level and when it will level up. Experience is primarily earned via defeating enemy Pokémon, though can be earned by other methods such as the Joy Ribbon. A player can see their active Pokémon's current and needed experience in the menu, or the team panel shown by a percentage. When in a party, the explorer kit's party tab shows the experience percent of any party members. Experience will be gained by each member in a party when a Pokémon is defeated.

Each Pokémon has a base experience yield when defeated. They are in line with the yields in the main series games. Level of defeated Pokémon is also a factor in how much experience is gained on defeat. Experienced gained is halved when a Pokémon is defeated using only the basic attack, meaning the use of no moves or items. No experience is gained if a Pokémon faints due to indirect sources of damage, such as non-volatile status conditions, move recoil, weather, or mini-counters.

Level
Pokémon will level up when the experience threshold for their current level is met. The highest level a Pokémon can be is 100. Level in Pokémon Mystery Universe has a factor in damage dealt, stats, and recruitment chance. Many Pokémon need to be at a certain level in order to evolve, or learn moves. A Pokémon's level can be seen in the team panel or Chimecho Assembly. Dungeons can temporarily change the levels of the Pokémon in the team, or disable gain of experience.

Players cannot directly see each other's levels, however when a player is clicked, a message will show in the chat, saying that the Pokémon is either "much" or "slightly" more or less experienced than you, or has about the same experience, depending on your active Pokémon's level.

! style="background-color:#"|Level Difference ! style="background-color:#"|Message
 * - style="background:#"
 * rowspan=2|5 or less
 * This Pokémon appears to be slightly more experienced than you.
 * - style="background:#"
 * This Pokémon appears to be slightly less experienced than you.
 * - style="background:#"
 * rowspan=2|6 or more
 * This Pokémon appears to be much more experienced than you.
 * - style="background:#"
 * This Pokémon appears to be much less experienced than you.
 * - style="background:#"
 * None
 * This Pokémon seems to be about as experienced as you.
 * }

Leveling up can be prevented for the active Pokémon if it holds an Everstone. Level can be decreased or increased if a Doom Seed or Joy Seed is consumed by the active Pokémon.

Experience Per Level
Each Pokémon has their respective experience group, but each experience group uses the required experience from the medium slow group. The table below shows the amount of experience needed to level up from the respective level.

! style="background-color:#" data-sort-type="number" |Level ! style="background-color:#" class=unsortable |Experience
 * - style="background:#"
 * 1
 * 4
 * - style="background:#"
 * 2
 * 8
 * - style="background:#"
 * 3
 * 16
 * - style="background:#"
 * 4
 * 27
 * - style="background:#"
 * 5
 * 38
 * - style="background:#"
 * 6
 * 99
 * - style="background:#"
 * 7
 * 155
 * - style="background:#"
 * 8
 * 215
 * - style="background:#"
 * 9
 * 339
 * - style="background:#"
 * 10
 * 437
 * - style="background:#"
 * 11
 * 543
 * - style="background:#"
 * 12
 * 651
 * - style="background:#"
 * 13
 * 783
 * - style="background:#"
 * 14
 * 943
 * - style="background:#"
 * 15
 * 1136
 * - style="background:#"
 * 16
 * 1368
 * - style="background:#"
 * 17
 * 1647
 * - style="background:#"
 * 18
 * 1983
 * - style="background:#"
 * 19
 * 2388
 * - style="background:#"
 * 20
 * 2876
 * - style="background:#"
 * 21
 * 3463
 * - style="background:#"
 * 22
 * 4170
 * - style="background:#"
 * 23
 * 5021
 * - style="background:#"
 * 24
 * 6047
 * - style="background:#"
 * 25
 * 7281
 * - style="background:#"
 * 26
 * 8768
 * - style="background:#"
 * 27
 * 10558
 * - style="background:#"
 * 28
 * 12713
 * - style="background:#"
 * 29
 * 15309
 * - style="background:#"
 * 30
 * 18434
 * - style="background:#"
 * 31
 * 22197
 * - style="background:#"
 * 32
 * 26729
 * - style="background:#"
 * 33
 * 32186
 * - style="background:#"
 * 34
 * 38757
 * - style="background:#"
 * 35
 * 46670
 * - style="background:#"
 * 36
 * 54000
 * - style="background:#"
 * 37
 * 55500
 * - style="background:#"
 * 38
 * 57000
 * - style="background:#"
 * 39
 * 58500
 * - style="background:#"
 * 40
 * 60000
 * - style="background:#"
 * 41
 * 61500
 * - style="background:#"
 * 42
 * 63000
 * - style="background:#"
 * 43
 * 63605
 * - style="background:#"
 * 44
 * 68147
 * - style="background:#"
 * 45
 * 72900
 * - style="background:#"
 * 46
 * 77868
 * - style="background:#"
 * 47
 * 83058
 * - style="background:#"
 * 48
 * 88473
 * - style="background:#"
 * 49
 * 94119
 * - style="background:#"
 * 50
 * 100000
 * - style="background:#"
 * 51
 * 106120
 * - style="background:#"
 * 52
 * 112486
 * - style="background:#"
 * 53
 * 119101
 * - style="background:#"
 * 54
 * 125971
 * - style="background:#"
 * 55
 * 133100
 * - style="background:#"
 * 56
 * 140492
 * - style="background:#"
 * 57
 * 148154
 * - style="background:#"
 * 58
 * 156089
 * - style="background:#"
 * 59
 * 164303
 * - style="background:#"
 * 60
 * 172800
 * - style="background:#"
 * 61
 * 181584
 * - style="background:#"
 * 62
 * 190662
 * - style="background:#"
 * 63
 * 200037
 * - style="background:#"
 * 64
 * 209715
 * - style="background:#"
 * 65
 * 219700
 * - style="background:#"
 * 66
 * 229996
 * - style="background:#"
 * 67
 * 240610
 * - style="background:#"
 * 68
 * 251545
 * - style="background:#"
 * 69
 * 262807
 * - style="background:#"
 * 70
 * 274400
 * - style="background:#"
 * 71
 * 286328
 * - style="background:#"
 * 72
 * 298598
 * - style="background:#"
 * 73
 * 311213
 * - style="background:#"
 * 74
 * 324179
 * - style="background:#"
 * 75
 * 337500
 * - style="background:#"
 * 76
 * 351180
 * - style="background:#"
 * 77
 * 365226
 * - style="background:#"
 * 78
 * 379641
 * - style="background:#"
 * 79
 * 394431
 * - style="background:#"
 * 80
 * 409600
 * - style="background:#"
 * 81
 * 425152
 * - style="background:#"
 * 82
 * 441094
 * - style="background:#"
 * 83
 * 457429
 * - style="background:#"
 * 84
 * 474163
 * - style="background:#"
 * 85
 * 491300
 * - style="background:#"
 * 86
 * 508844
 * - style="background:#"
 * 87
 * 526802
 * - style="background:#"
 * 88
 * 545177
 * - style="background:#"
 * 89
 * 563975
 * - style="background:#"
 * 90
 * 583200
 * - style="background:#"
 * 91
 * 622950
 * - style="background:#"
 * 92
 * 643485
 * - style="background:#"
 * 93
 * 664467
 * - style="background:#"
 * 94
 * 685900
 * - style="background:#"
 * 95
 * 707788
 * - style="background:#"
 * 96
 * 730138
 * - style="background:#"
 * 97
 * 752953
 * - style="background:#"
 * 98
 * 776239
 * - style="background:#"
 * 99
 * 800000
 * }

Training
Training is an action that involves repeating dungeons for the sole purpose of gaining experience points and levels for the desired Pokémon. While considered a game mechanic it isn't referenced specifically in the game itself.

Items
Generally training involves use of items to increase experience gain. Their experience boost affects all team members when held, and have an effect even when held by a Pokémon that has Klutz. Available items include: There are some held items that give +50% experience, but are only active during certain times of the year: They're usually obtainable from the Seasonal Shop or Holiday Cave that's running at the time of their activation.
 * Beginner Band [[File:Pink_Band.png]]. Gives a +5% experience boost, and also gives the holder +5 to all stats (excluding HP). Obtained from Grassroot's Kecleon Shop, in exchange for 1,000 Poké.
 * Wonder Chest [[File:Wonder_Chest.png]]. Gives a +10% experience boost. Obtained from Meesa's Shard Exchange at the Greenport Bazaar in Archford, in exchange for 125 Yellow Shards. Also obtained from any Tanren Chambers B99F exit, and as a drop from Mew in Mysterious Jungle.
 * Miracle Chest [[File:Miracle_Chest.png]]. Gives a +20% experience boost. Obtained from Tanren Chambers Normal B99F exit's Grand Box, and the end boxes of Sky Fortress' Garden path.
 * Heart of Chocolate [[File:Sweet Heart.png]], during February/Valentine's Day.
 * [[File:Easter Egg.png]], during April/Easter.
 * Sleigh Bell [[File:Sleigh Bell.png]], during December/Christmas.

There are also family items for certain Pokémon families that increase experience gain by +10%. A full list can be found here. These items must be kept in the bag like all other family items. Held items that boost experience stack with family items, but not with other held items. If two or more experience-boosting items are held, the effect is cancelled out completely.

Training also commonly involves use of items to increase Pokémon spawns:
 * Honey [[File:Honey.png]] is a consumable item that spawns five Pokémon randomly across the floor upon use.
 * Summon Traps [[File:SummonTrapItem.png]] are a consumable item that place down a Summon Trap, which spawns five Pokémon when stepped on by an enemy Pokémon, typically surrounding the trap's activation point. Obtained primarily from Tanren Chambers and Gabeedle's Shop.

Dungeons
Dungeon choice for training is most commonly influenced by length, difficulty of completion and type advantage. For recommendations, see Good Training Locations.