The Null Hypothesis is an adult Ren'Py adventure and dating sim by Ron Chon, set in an X-Men-inspired mutant school. You play a male mutant whose powers surface after an attack by an ancient malevolent entity, then join Charles Xavier’s academy to learn control. The 2D animated cast includes Storm, Rogue, X-23, and Jean Grey, all single, and your choices during scenes, events, and exploration can shift how they respond to you while global conflicts test growing relationships.
The current v0.9b build, dated April 6, 2026, is still under development and runs uncensored in English on Windows, Mac, and Android. The update expands debrief events after cheating, with unlockable replay-menu options, adds new adult trigger events and reactions for Rogue, Laura, and Jean, and introduces a Kurt-taught mediation system for repairing poor pair relationships. Cecilia Reyes’ standing model is added for gradual sandbox inclusion, and GPU-optimized textures improve loading while increasing build size.
Developer's description
This is an adventure/dating sim game set in the X-Men universe and written in Ren’Py. We are drawing heavy inspiration from the comics.
Spoiler
You are a mutant whose abilities emerge in dramatic fashion when you are attacked by an ancient and malevolent entity. You are taken in by Charles Xavier, who runs a school for mutants with the goal of protecting them and helping them learn to control their powers.
Upon arriving at the school, you meet a host of characters fulfilling different roles at the school, including Storm, Rogue, X-23, and Jean Grey.
You quickly learn that all of these characters are… single. Some are interested in you from the start; others think you are beneath them. Through various interactions, scenes, and events, you can change how the characters view and respond to you.
As you explore the school and your growing powers, global events will transpire that test the strength and nature of your budding relationships.
Review notice: Please do not mention other games.
v0.9b
<cheating events>
- fleshed out aftermath/debrief events for cheating on a character
- unlockable in the replay menu for those who don't want to trigger the normal way
<breeding kink>
- new trigger events and accompanying narrations/reactions/interactions for Rogue, Laura, and Jean
<group mediation events>
- new system for repairing poor relationships between pairs of characters
- tutorial by Kurt
<Cecilia Reyes>
- her standing model has been added to the game, and she will be gradually added into the sandbox in a similar fashion to Charles
<GPU-optimized textures>
- per Patreon poll, we're building with textures that are GPU-optimized to reduce the memory load on the image cache and improve loading times
- this has the downside of increasing build size by ~2x
<combat minigame>
- can currently be accessed in the Danger Room upon completion of the Ch. 1 summer finale
- beta stage with a handful of predefined scenarios
- tutorial by Storm
<new silhouettes>
- both Patreon and background
<foot content>
- more narrations/dialogue to accompany foot content
v0.9a
<new art for Ch. 1 characters>
- kissing, cuddling, and cunnilingus cutouts
- standing male layers updated (including headpats)
- new hair styles
- face piercings
- tattoos
- customizable eyeshadow and lipstick color
- skimpy swimwear
- armpit and thigh body hair options
- proper frame-based leaking animations
<new locations>
- attic hallway
- rec room
- basement hallway
<improved ambient lighting>
- sunrise vs. morning
- evening vs. sunset
- clear skies vs. raining
<replay system>
- simulate previously experienced key events in the Danger Room
<improved color changing>
- display current numerical value
- edit brightness, contrast, and saturation
- automatically reset values
<spunk stains>
- spunk layers now have a "stain" effect on clothing layers while remaining gooey on skin
<guitar practice>
- once you have access to a guitar, you can practice to build your skill!
- serenading a character can impress them or lead to awkward encounters depending on your skill
<location submodules>
- mostly of interest to modders: we've split locations off into submodules that act independently of the main game code, facilitating easy modification and addition of locations
- modifying the available actions at each location and adjacencies of locations is also much easier
<import/export outfits>
- new buttons in the bottom right of the wardrobe interface allow you to import/export outfits for transfer between saves
- export button saves the current outfit to the /Outfits/ directory created in the saves folder
- import button loads all outfits in the /Outfits/ directory of the saves folder and adds them to their respective character's wardrobe if the character owns all necessary items
<import/export saves>
- options in save/load screen for importing and exporting saves and persistent data
- works on Android, exports to externally-accessible directory
- does not overwrite existing saves
- also imports/exports persistent data and outfits in save directory (does not overwrite either)
<trivia events: classroom and strip study>
<automatic coverage/visibility detection>
- makes it possible to identify when things like body parts and layers are visible for specialized reactions, without tedious labeling/tagging
<live2d, background, and interface optimizations>
- offset detection of layeredimages for automatic texture placement
- auto-detection of clothing states and incompatibilities based on model
- aggressive memory optimizations enabling higher resolution textures
- extensive interface optimizations
<image load multi-threading>
- configurable in the graphics menu! should significantly speed up game loading and reduce hitching
- will likely decrease performance on Android devices - keep set to "1" to disable
<fine-grained resolution control>
- experiment with different options to see what maximizes stability on your device
<QoL/accessibility>
- screenshake can now be disabled alongside flashing lights
- temperature can now be reported in Celsius, Fahrenheit, or Kelvin
- remote vibrator UI is now draggable
- platonic hugs and other interactions that can be reasonably interpreted as platonic do not trigger cheating events
- pre-emptively delaying orgasms and mutual orgasms now possible with button press
- zoom/pan feature in sex screen
<lots of bugfixes>
v0.8c
<interaction overhaul>
- sandbox reactions are now handled by an overhauled system that attempts to achieve more natural and diverse reactions through natural combinations of generic and specific dialogue
- system is designed to support both modding and translation efforts, and it is trivial to add new interactions into the pool
<event revisions>
- significant revisions of both story and character events to facilitate platonic playthroughs, quirkless playthroughs, kink-heavy playthroughs, and everything inbetween
<petnames>
- characters can now have multiple context-dependent petnames, including sexy and private ones
<quirks>
- characters can now have more than two quirks, and it's easier than ever to add your own in
<sex experience>
- new system for characters becoming more experienced and accordingly confident in sex contexts, including robustification of oral and anal training as well as experience dirty talking and overall sexual experience
<database update>
- the database interface has been tweaked and now includes a ton of entries that can be accumulated over the course of a Ch. 1 playthrough
<performance tweaks>
- alternate strategy for checking for Live2D updates with less dependence on threading. should be more performant on Android and lower-spec devices and comparable on higher-end devices
<soundtrack updates>
<many bugfixes>
v0.8b1
<performance tweaks>
- more graphics settings for tuning performance to a given device, with device-sensitive default settings
- low resolution setting now scales nearly all assets to 50% resolution
- Android-specific tweaks to reduce lag
- tuning image compression for quality/load time balance
<bugfixes>
- "I Studied the Blade" should properly unlock now. make sure you have actually won the leaderboard at least once in the season (and have never lost it). the achievement should unlock at the start of the next season
v0.8b
<performance tweaks>
- more graphics settings for tuning performance to a given device, with device-sensitive default settings
- low resolution setting now scales nearly all assets to 50% resolution
- Android-specific tweaks to reduce lag
- tuning image compression for quality/load time balance
<bugfixes>
v0.8a
- New CGs with events, multi-frame animations, x-ray, sweaty effects
- Pool party
- Modular dates with new kitchen module
- More dirty talking and flirting options
- Gift tweaks
- New locations and background art
- New graphics options for performance tuning
- Optimizations to Live2D
- Bugfixes
v0.7b
- Remastered Ch.1 finale events
- Bugfixes
v0.7a
- Ch. 1 Summer finale event
- Dirty talking system
- Optimizations to Live2D
- Bugfixes
v0.6b
- Sex system update
- Low memory mode
- Interface updates
- Improvements for modders
- More options in game menu and character customization
- Optimizations to interfaces
- Bugfixes
v0.6a
- New art (revised and Live2D animated sex poses for Rogue, Laura, and Jean)
- Real-time physics processing
- Slice of life events
- Reputation system and Institute leaderboards to track and reward personal progress
- New abilities, skills, and achievements
- Achievement shop
- Group activities and chat
- Random texting
- Various UI updates and improvements
- Dynamic outfits (mostly for default outfits)
- Optimizations to Live2D rendering and screens
- General bugfixes
v0.5b
- New art (Rogue's blowjob pose; outfits and hairstyles for Rogue, Laura, Jean)
- Clothing should be done for all standing poses, complete with dialogue reactions
- Infidelity system overhaul to address bug reports
- Seasonal skill and level caps lifted
- Toggleable key items
- Optimizations to Live2D rendering, autosaves, and rollback
- General bugfixes
v0.5a
- Quirk overhaul (modularity, customization, encouraging/discouraging tweaks)
- New clothing for Rogue, Laura, Jean
- Relationships menu tab
- General bugfixes
v0.4b
- New art (Rogue's doggy pose; outfits for Rogue, Laura, Jean; Juggernaut event)
- New Mutant-tier silhouettes
- Clothing shame rebalance
- General bugfixes and QoL changes
v0.4a
- Standing sprites (subtly) animated in Live2D
- Polyamory and friendship system
- Giving/receiving room keys
- Stat rebalance
- General bugfixes and QoL changes
v0.3d
- New art (outfits for Rogue, Laura, Jean)
- Color changing (wardrobe items, hair/body hair, Player skin color, tanning)
- First part of friendship system (greetings change according to characters' relationship)
- General bugfixes and QoL changes
v0.3c1
- Bugfixes for most common reported errors
v0.3c
- New art (classroom, Rogue's missionary pose)
- Rogue's missionary pose animated in Live2D
- First Mutant-tier silhouette
- Sex system logic tweaks
- New optional events in Chapter I: Summer for Rogue, Laura, Jean
- General bugfixes
v0.3b
- New art (new outfit for Laura, accessory layers)
- Standing sprites implemented in Live2D (no new animations yet)
- Quality of life improvements
- Tweaks to outfit customization
- Customizable names and petnames
- Interface tweaks
- New optional events in Chapter I: Summer for Rogue, Laura, Jean
- General bugfixes
v0.3a
- Gameplay overhaul to reduce grind
- New character-specific optional events
- Standing art upgrade
- Overhauled sex minigame
- New UI
- Level progression with skill tree
- Achievements
- New phone apps
- Dynamic background rendering
- General optimizations and bugfixes
v0.2b
Not available.
v0.2a
Not available.
Preview
- Prologue and first three (linear) days at the school.
Player reviews
Player rating5.0 / 5 · 20 ratings
Written reviews20 · avg 4.3★
Positive (4–5★)75%
Latest review2026-03-29
What players say
Most reviewers rate it highly for art and characters, despite grind and pacing complaints.
5★11
4★4
3★4
2★1
1★0
Players like
Beautiful art and attractive character designs
Distinct personalities and well-written romantic interactions
Engaging story and character progression
Customization and interactive dating-sim features
Common complaints
Grindy sandbox and map backtracking feel tedious
Female expressions can feel flat and personality-free
Update cycles are long and content feels delayed
Best for players who like X-Men parody dating sims with strong art.
Summarised from 20 written player reviews.
Goonfin2026-03-29★★★★★
Traditional gooner art was a thing of legends (no not that scam game) but not anymore, these devs have brought it back with a decent go at X-MEN. One of the most polished 2D games with a smooth Ui and…
Mwanted2026-03-28★★★★★
Ok, my feedback after playing a little more: - Already ages ahead of the game it takes inspiration from, and the potential is not even comparable. - Art is perfect, I don't know how else to express it. There's work…
NoxUberholen2026-03-16★★★★★
I am not allowed to name the other game(s), but let me tell you that, as someone who knows X-men from the movies and *another* dating sim game, this is something that you wanna try playing BUT only with a…