[[caption-width-right:240:LiteralSplitPersonality, in action.]]
The next Creator/CompileHeart game developed under the direction of Keiji "Shin" Inafune (no, [[Franchise/MegaMan not that one]]).

The plot revolves around Chou Chou, [[AGodAmI a self-proclaimed god]] who wishes for [[TakeOverTheWorld world domination]].

It was released in Japan on March 22, 2012, and by [[Creator/NipponIchi NIS America]] in Europe on September 28th, 2012 and in the U.S. on October 16th, 2012.

Not to be confused with ''{{VideoGame/MUGEN}}'' ([[{{Crossover}} though somebody might put this game's characters in there if they haven't already]]).

NOTE: Character page currently under construction.

A sequel was released, entitled ''"Mugen Souls Z"'' detailing the adventures of Syrma, who wants to become the "Ultimate God" once again with the help of Nao and Chou Chou.
!! Tropes Associated with the first game, ''Attouteki Yuugi Mugen Souls''

* AbsurdlyHighLevelCap: Trailers show that 9999 is the highest level you can obtain in this game.
** [[UpToEleven Absurdly]] [[{{HSQ}} High]] [[{{Cap}} Damage Cap]]: Trailers show multi-hit attacks easily breaking ten-digit damage. At one point, a finishing move is shown to cause a grand total of ''over six-and-a-half '''billion''' HP damage''! Even for a Nippon Ichi-associated RPG, I think that's a new record! [[note]]Disgaea games since have reached quadrillion damage counts, and the first time you cause damage at this level in Disgaea 5, a trophy pops.[[/note]]
** One of the screenshots on the website shows an attack doing over '''933''' ''billion'' damage.
* AmnesiacGod: Chou Chou has no idea who she is other than knowing that she's a god.
* BittersweetEnding: [[spoiler: The Normal Ending. Chou-Chou abandons her peons in order to destroy Vorgis for good. While a post-credits scene shows they eventually found her somewhere at the edge of the universe, and can speak with her, she is unable to come back with them. Thankfully, it seems this ending isn't canon.]]
* {{Bowdlerize}}: NISA decided to remove a mini-game that has controversial elements in it to avoid the [=AO=] [=ESRB=] rating ([[http://nisamerica.com/forum/viewtopic.php?f=64&t=9704 as discussed by a mod]]).
** The PC port was going to avert this until Ghostlight was instructed by Steam that they could not keep the mini-game.
* CallingYourAttacks: A variation with Soul. When casting a spell, he'll say "Spell" and then just say whatever it does. Such as "Spell! That magically teleports me safely to the castle!" Or "Spell! That heals all wounds in a flash of light!".
* CensorSteam: Necessary for the various bath scenes, and in the Japanese version, a small extra mechanic to the hot spring minigame.
* CharacterCustomization: [[RuleOfThree Trailers show]] that you're able to create different characters.
** You can customize the clothing of everyone in the playable party, including the main characters.
* CloningBlues: [[spoiler: A few of your party members get cloned for some bizarre reason in the post-game and you must fight them with their levels in the 1000 range. Good luck with that by the way, unless you've been LevelGrinding at the Mugen Field.]]
* CoolShip: The [[{{Engrish}} Gcastle]]
* CrushBlush: Ryuto gets this all the time when someone pokes fun of his crush on Chou-Chou.
* DaddysLittleVillain: Subverted, [[spoiler: Vorgis is NOT Belleria's father afterall, and she isn't much of a villain.]]
* DefeatMeansFriendship: Every single boss fight ends with Chou-Chou having the defeated person as their slave.
* DepartmentofRedundancyDepartment: The 7th World is called "Earthen Soil World". Gee, might as well say "Planet Planet Planet".
* DiscOneNuke: it's pretty easy to wander into the Mugen Field at early levels, get into a random ship battle and get a huge EXP bonus, propelling your party forward 20 levels or more, pretty much steamrolling the rest of the main story for a time.
** Generally that could be bad, but in a game where you can increase the level way higher than you should, it's a pretty good thing.
** The equipment in some of the DLC packs are endgame level in terms of power and can be used as soon as you buy the DLC which can make the early levels a complete cakewalk. The Steam version of the game goes even further as it comes with some of said DLC packed into the base game.
* DifficultySpike: Chapter 8. And it only gets harder from there.
* DoesThisRemindYouOfAnything: [[spoiler: Beat the clones of your party members in the post-game of the GoldenEnding (good luck with that by the way) and look at the CG picture.]] That is all.
** Also, the CG images that show up whenever someone goes into Syrmas coffin.
* DuelBoss: [[spoiler: Chou-Chou has a one-on-one match with Belleria.]]
* ElementalRockPaperScissors: Personalities in Mugen Souls act as elements, and have corresponding strengths and weaknesses. Incompatible personalities will reduce the power of team attacks, adding a certain degree of strategy to party formation.
* EpicFail: InUniverse, Altis failed so hard at being a demon that she was reincarnated as an angel instead.
* {{Expy}}: [[spoiler: Chou-Chou's true form really looks like [[Anime/PuellaMagiMadokaMagica Goddess Madoka]] albeit with more...[[LampshadedDoubleEntendre filling.]]]]
** Ryuto has the same look, temperance and even English VA as Almaz, from Disgaea 3. (Who was also designed by Takehito Harada).
** Syrma has the same personality and [[Creator/CheramiLeigh English VA]] as [[VideoGame/HyperdimensionNeptuniaVictory Plutia]]
** Also Reu is a young child who has a surprising amount of energy and strength just like [[VideoGame/HyperdimensionNeptuniaVictory Peashy]]
* ForgottenFriendNewFoe: [[spoiler: Belleria is Chou Chou's first friend and she forgot all about it.]]
* GuideDangIt: Getting the True Ending in typical Compile Heart fashion.
** Granted, they do give you some ideas on how to get it after getting the Normal End, but figuring out what the threshold is is up to you.
** [[spoiler: 20% average charmlevel and at least 19% on all personalities. FYI.]]
* GivingSomeoneThePointerFinger: Chou-Chou loves doing this all the time. To a lesser extent, so does Altis.
* HappinessInSlavery: Ryuto. To the max. This guy will never stop serving Chou-Chou if he can help it. Admittedly, Chou-Chou isn't a particularly harsh master... Most of the time...
* HatesBeingAlone: [[spoiler: Chou-Chou. It the reason she created her world in the first place. She became even lonelier after realizing that she was only an observer of the world she made, not a participant.]]
* HoistByHisOwnPetard: [[SchmuckBait Go ahead, go overload]] that [[EnergyBall Peon Ball]]. [[TotalPartyKill We'll wait to see]] your reaction.
* HotSpringsEpisode: Brings back the good ol' fashion minigames from ''VideoGame/RecordOfAgarestWar2''
** Unusual for Compile Heart, this happens ''at the beginning of the game''.
* InformedAbility: Chou Chou Sadistic personality is actually not a real sadistic in fact she's more like of an arrogant queen, a real sadistic would be her Terse personality who shows absolute zero compassion to others and even [[TooKinkyToTorture managed to save Shirogane by torturing him so much that it excites him.]]
** NISA has confirmed they are making significant changes to the character in order to make her more sadistic to a western audience.
* KnightOfCerebus: [[spoiler: Vorgis. Enough said.]]
* LauncherMove: Some skills enable you to launch enemies up in the air.
* LevelGrinding: Say hello to the [[BonusDungeon Mugen Field]].
* LiteralSplitPersonality: Chou-Chou Infinite has split herself up into seven different personalities: [[TheDitz Ditz]], [[GenkiGirl Hyper]], [[YamatoNadeshiko Graceful]], [[ElegantGothicLolita Terse]], [[AbusivelySexyWoman Sadistic]], [[TooKinkyToTorture Masochist]], and [[{{Tsundere}} Bipolar]].
* MarshmallowHell: [[spoiler:In the ending, Belleria is hanging out at Chou-Chou's cleavage, who's now grown HUGE.]]
** Never shown on-screen, but it's implied Chou-Chou ran face-first into Marina's chest when they first met.
* MontyHaul: If you download the {{DLC}}; it's a Compile Heart tradition after all.
* NoseBleed: Ryuto makes one at the beginning of the game when he sees Chou-Chou and Altis naked in the bath. In fact, he gets these a lot.
* OneWingedAngel: [[spoiler: Vorgis gets a second form when he eats Belleria's gemstone to fuse with her to become a God of Destruction.]]
* PersonOfMassDestruction: Chou-Chou, the protagonist, is able to literally drop an EnergyBall ''[[UpToEleven the size of a freaking]] [[http://www.youtube.com/watch?feature=player_embedded&v=4EqZ6WXbAGw galaxy!]]''
* PragmaticAdaptation: Nippon Ichi has announced some changes will occur to the US version of the game, presumably this will involve removing or editing the extremely lewd bathing minigame. [[spoiler: And possibly the post-game post-fight CG of clones of your allies.]]
** Confirmed. NISA has stated the bathing mini-game will be removed in it's entirety.
*** For more info on this (and link about it), see {{Bowdlerize}} above.
* SequelHook: [[spoiler: The game ends with Chou-Chou declares her new ambition to rule the entire universe. And Altis still wish to become a demon even after promoted into an even higher rank Angel.]]
* ShoutOut: Lots.
** The trailer ends with a [[Anime/DragonBallZ Peon Ball]]. The size of a ''Galaxy''. [[UpToEleven That does 8.9 billion damage.]]
** In Z, after a while an NPC named [[Franchise/FridayThe13th Jason who is wearing a hockey mask]] appears.
** One of the twin swords you can can use is named [[VideoGame/{{Okami}} Amaterasu after the sun goddess and uses a similar colour scheme]].
* SpellMyNameWithAnS: Even the website ''and'' the game can't seem to agree whether it's Shu-Shu or Chou-Chou. However, the official translation is the latter.
** It should be noted that it's pronounced "Shu Shu" either way.
* SpiritualSuccessor: It's basically a ''VideoGame/HyperdimensionNeptunia'' game. Of course ''Creator/NipponIchi'''s American branch is publishing it overseas...
* TacticalRockPaperScissors: How the ship-to-ship combat works in this game.
* ThemeMusicPowerup: When entering Fever Mode, you are treated to the game's themesong overriding the battle theme for as long as the Fever Mode lasts.
* TheStarscream: [[spoiler: Vorgis to Belleria.]]
* UnknownRival: Well, more like "unacknowledged rival". Alys thinks she's Chou-Chou's rival, and while Chou-Chou does pity her, she knows that she is infinitely superior.
* WhatHappenedToTheMouse: [[spoiler: You never do get to actually visit/conquer Soil World. While it is freed from Vorgis' stomach in both endings, Chou-Chou and company never actually go there in the story or the postgame.]]
* WordSaladTitle: If you must know, the literal translation of this game is "Overwhelming Game Infinite Souls".
* YouAreNotAlone: [[spoiler: The group gives Chou-Chou this treatment when she recalls how lonely she was as a god.]]

!! Tropes Associated with the second game, ''Mugen Souls Z''
* AttackOfThe50FootWhatever: Peon Ball is replaced with Ultimate Soul, which summons a Chou Chou whose size varies based on Syrma's charm levels.
* BreakingTheFourthWall: After defeating [[spoiler:Fake Ace]] Bellaria asks the player if they would want a reward for [[spoiler: beating all of the clone characters]].
* DemotedToExtra: Chou-Chou loses her powers and gets shrunk down to a tiny chibi form in the beginning, handing the playable character status to Syrma.
* DifficultySpike: [[spoiler:The very first "forced" encounter in the post-game consists of enemies with levels much higher than the TrueFinalBoss.]]
* FetchQuest: Many of the Planet Spots require this; instead of asking the player for enough money to buy an item (as in the first game), they now ask for the item directly.
* {{Flanderization}}: Zigzagged. Some characters' personality traits are downplayed (such as Alys losing much of her ValleyGirl speak), while others are exaggerated (such as Marina's clumsiness).
* FunSize: Chou-Chou gets shrunk down after losing her powers because of Syrma's coffin malfunctioning.
* ImTakingHerHomeWithMe: While Reu and [[spoiler:Fake Reu]] are playing together Tsukika askes Shirogane if she can take [[spoiler:Fake Reu]] with her.
-->'''Tsukika:''' Um... Mister Shirogane...?
-->'''Shirogane:''' No.
-->'''Tsukika:''' I-I didn't say anything yet!
-->'''Shirogane:''' You want to take the other one with us. No way.
-->'''Shirogane:''' One is enough of a handful already. There's no way we can handle [[spoiler:two]].
-->'''Tsukika:''' I-I'll take care of [[spoiler:them both]]. I'll make sure to feed her, and walk her every day...!
-->'''Dees:''' [[LampshadeHanging It sounds like they're talking about a dog...]]
* LateArrivalSpoiler: The game is a direct sequel, so this is to be expected. For starters, anything regarding [[spoiler:Belleria]].
* PermanentlyMissableContent: [[spoiler:The twelve worlds are destroyed in the Normal Ending, denying the player access to ''anything'' except the G-Castle, Mugen Field and the option to start NewGamePlus.]]
* WesternZodiac: The theme for the twelve worlds.