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RPG Maker MV
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Version: 0.8

Version: 0.7.2

Version: 0.6.4

Version: 0.5.2

Version: 0.4.2

Version: 0.3.1

Version: 0.2.4

Version: 0.1.3

The Proteus Effect
by Proxxie




The Proteus Effect is a game for adults that combines lighthearted comedy, engaging characters and story, lively dialogue, and gripping challenges with distinctive, vivid art and alluring erotic scenes to create a fun, sexy, and ultimately unique experience.

You take on the role of Alex, a lovable but dimwitted young man who barely graduated college and is now desperately searching for a job. Just in the nick of time, he stumbles into the job of his dreams as a video game tester for a virtual reality startup, but all isn’t as it seems. After being introduced to his eccentric coworkers, he soon finds himself not only trapped in the virtual world, but also stuck in the body of a nubile young woman.

All Alex wants is to return home to his own body, but he winds up reluctantly embarking on an adventure through a series of fantasy worlds, including the company’s game world, another world that’s suspiciously similar to a popular MMO, and an assortment of others. 

He isn’t alone, though - shortly into the journey he is joined by his co-worker Ana, a tough, slightly abrasive, yet kindhearted young woman. Alex isn’t the only one who’s changed in the virtual world; it looks like Ana ended up with a little something… extra?

 Eventually, Alex is joined by other quirky companions, and together they try to uncover what’s behind the system’s strange malfunctions. How does he keep getting sent to these bizarre places? What connects them all? Can he ever manage to find his way back home?

This is a game for adults, so there’s plenty of erotic content. This isn’t just mindless porn, however - the scenes are sometimes titillatingly erotic, sometimes hilarious, but always interesting and fun. The game currently has content for futanari fans, and there will be plenty of scenes for people who like ‘group activities’, monsters, tentacles, vanilla (gasp!), and many other fetishes. The erotic scenes are completely optional - you can avoid any scenes you don’t like, and if you just want to experience the game’s entertainment without any of the porn, you can do that too!

If you’re looking for a fun, entertaining, and sexy game with likable characters, laughs, and distinctive art, The Proteus Effect might just be your game. So go ahead, give the public version a try! It’s only one major release behind the patron version, and it’s free! And if you really enjoy the game - and I think you will - please consider supporting the project by becoming a patron. 

Also, feel free to join us on Discord

Note: The download links in the sidebar are for Windows. For public macOS and Linux releases, please see my Patreon page (also available on SubscribeStar.)


Current Patron version: 0.9

Playable content:

  • 2 new H-scenes
  • 7-ish quests, depending on how you count
  • 1 (small) dungeon
  • 2 boss fights
  • 1 minigame
  • new district
  • Several new skits


  • 60 new images (31 H-scene images, 29 character view images)
  • Many new portraits

Features and misc:

  • New party member
  • Added lighting effects
  • Added game character view feature (press 'i' to toggle. Warning: this feature is a little wonky!)
  • Added menu character view feature (on the Status menu)
  • Xmog feature (he's on the 2nd floor of the Sorcerer's Society)
  • Battle action sequences
  • New animations
  • New ability for Ana
  • New equipment slots
  • Default items for new slots (old saves should be fixed automatically)
  • New boots for completing Celie's quest (chickens vs. frogs, awarded retroactively)
  • Changed the way TP behaves for many characters
  • Removed lots of exclamation points!!
  • Got rid of level indicators
  • Improved conveyance for cookie quest (there should be fewer 'WTF am I supposed to do?' moments.)
  • Probably lots of stuff I missed


Current public version: 0.8

0.8 Changelog:

  • 6 new areas with 31+ new maps
  • 7 new quests
  • 2 new minigames
  • Ana texture revamp
  • 1 new H-scene with 29 images
  • Many new characters and skits
  • Difficulty revamp for The Dark Pits
  • Added Karathian Alarm Clock to help with getting nighttime H-scenes
  • Bugfixes, other minor changes


  • 6 new areas with 31+ new maps
  • 7 new quests
  • 2 new minigames
  • Ana texture revamp
  • 1 new H-scene with 29 images
  • Many new characters and skits
  • Difficulty revamp for The Dark Pits
  • Added Karathian Alarm Clock to help with getting nighttime H-scenes
  • Bugfixes, other minor changes



  • Added the rest of The Dark Pits dungeon (incorporates difficulty revamp from 0.8)
  • Added 4 new quests
  • Added succubus H-scene (2 paths, one of which is futa x male)
  • Revamped H-scene progression: It is now easier to find many scenes, and some scenes that were impossible to get if you missed them the first time can now be obtained
  • Added starter for legendary quest chain!
  • Various bugfixes


--- A lot of stuff ---



Second dungeon should be less frustrating to players having problems with it.

HCG image quality slightly enhanced

Download size greatly reduced

Path to upper level in chincha area now more clearly marked

NUM 0 should now escape, for those playing with the number keys (hopefully, couldn’t test)

Various minor bugfixes


Added visual effects to healing minigame

Resolved issue that could trap players in the old adventurers' house

Resolved issue that could send players to level that shouldn't be in game

Saves are again located in save folder rather than local app data folder

Resolved issue that could cause healing minigame to restart after winning it

Resolved player character's strange fear of butterflies

Player can no longer move (and potentially softlock game) during dungeon cutscene

Resolved issue that could prevent some players from re-entering first dungeon

Resolved issue that could cause game to request nonexistent assets

Various minor bugfixes


Fixed crashes in the healing minigame and dungeon cutscene


Can no longer enter Celie & Elian's house before completing quest

Quest journal should show up as normal



New content:

New starter area

New dungeon

2 new H-scenes (one of which is 13 images)

Various quests

Various other areas

Lots of dialogue


Gameplay enhancements:

Added intro skip feature

Can now hide text boxes during H-scenes (press 'h' for hide)

Revised equipment and equipment screen

Player character sprite now changes according to outfit

Probably a bunch of other stuff I forgot



Resolved issue that could interfere with scripted scenes in dungeon

Resolved issue that could trap player in barn

Various minor fixes

Added Patreon link




Reduced some enemies' HP

Latest Reviews - View All Reviews

Review by love2suk

Version reviewed: 0.8 on 11/28/2020

love this game so fun and funny!  the tanking montage rocks! 

Review by parya

Version reviewed: 0.8 on 11/21/2020

you can spend whole evening and do not reach even for the second sex scene. So it is for some kind of fanats of this fighting games, difficult one

Review by JustSomeSissy

Version reviewed: 0.8 on 11/21/2020

This game is fun. Good isekai style gender change, characters are actually pretty funny. Good Hentai scenes, thought there are good amount of gaps between them. There isn't really fighting and you can mostly run through the dungeons without doing much, and the fights are easy if you don't. Good rpgmaker game I think.

Review by SUPERtwinky

Version reviewed: 0.8 on 11/17/2020

Loved this game, not just for the H content but also just as a game.  It's quite funny.
Also love the art style of the 3D models.
A solid 4/5

Review by dercas

Version reviewed: 0.8 on 11/16/2020

Super happy to see that this is still being developed!  Gorgeous art and witty engaging writing.  Keep up the great work!  Definitely one of my top five favorites on this site!

Total Games: 1,681
Total Contests: 32
Total Reviews: 15,993
Total Engines: 33
Total Adult Themes: 10
Total Transformation Themes: 26
Total Multimedia Themes: 9
Total Online Plays: 2,917,044

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