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Game Information
Release Date
Last Update
version a0.12-hotfix
Orig PC Gender
Adult Themes
TF Themes

Version: version a0.12-hotfix

Version: version a0.12

Version: version a0.11

Version: version a0.10 hotfix 1

Version: version a0.09-hotfix

Zeta Wave

A polio vaccine trial goes wrong in 1931, and the descendants of the students in the trial are all found to have the zeta chromosome. Every time the carrier of a Z chromosome has sex, he or she physically changes to the opposite sex. It is a biological discovery that will change the world. How will it change the world? That's up to you.

Story #1: The tale of Billy, a high school sophomore and all-around Boy Scout, who discovers he is a Zeta carrier for the first time. How will he deal with this ability? Will he come out to his friends, or will he try to keep it all a secret? 

Length per Twine UI: about 213K "words."

Note: I am disabling user reviews for the time being. Reviews are not the place for bug reports. This is an alpha release and advertised as such; there will be bugs. If you would like to report bugs so they can be fixed, please use the discussion thread.

Version va0-012-hotfix

  • Some game-breaking bugs repaired.
  • Some non-game-breaking bugs repaired.
  • Some bugs left in, for variety.

Version va0-012

  • Day 14 is now available.
  • The text and dialogue during dinner and bedtime on Day 13 has been edited (only when you are female).
  • A number of bugs related to the transformations on Day 12/13 have been hunted down and shot. Hopefully the scouting trip goes well now.
  • Some new tracking variables have been added around Day 8 through Day 11. These aren't new content, but they make a note of what state you were in when certain events happened. This means old game saves may not work. 
  • This update is around 47k "words," according to the Twine UI. That doesn't mean this update takes longer to play; it only means there are a large number of different ways the day can play out, depending on your previous choices.

Version va0-011

  • Fixed a spare DIV tag when you examine yourself as a girl on Day 12.
  • Added new dialogue on Day 3. If you are open about being a Zeta, you shouldn't be so worried that Dot will talk.
  • Added a new paragraph to describe bathing on Day 12, if you are secretly attending Boy Scouts as a girl.
  • The last event of Day 12 is now available — making out with Bonnie (or Melvin in FTM).
  • I have revised Bonnie (and Melvin)'s backstory to remove mention of alcoholism. The story didn't need it.
  • The transformation on Day 8 in the art room now includes a more varied array of descriptions for cock length.
  • The formula for calculating hair length (as a girl) has been revised to allow for faster growth. I may need to adjust the descriptions of long hair to account for this; if you see anything that looks wrong, let me know on the forum thread.
  • Day 13 is now available. There are a number of figure-altering decisions to be made here.
  • I have added a suggestion page for re-naming the main character (and the SO) with an era-appropriate name. The suggestions will automatically exclude any names that are already taken by NPCs.

Version va0-010 hotfix 1

  • Fixed link on Day 5 page, scout meeting, choose "volunteer" or "let someone else." Invalid variable method caused a crash.

Version va0-010

  • Completed almost all of Day 12, the first day of your scouting trip.
    • You may attend your original troop's trip, or the opposite-sex troop's trip if you confessed to your scout master and joined the other troop.
    • There is a mandatory transformation if you did not do the double-TG on day 11.
    • There is a possible optional transformation if you are not in the right shape to attend a scout trip that you're entitled to attend.
    • There are three superbonus decisions on this day. This day will be fairly influential to your final form.
    • The only missing scene is the "go to sleep" scene, which will contain another choice in certain paths.
  • Fixed an undefined reference to the gym teacher if you stay home from school.
  • Fixed continuity in the Double Secret TG scene. The Pep Squad and Marching Band scenes were mixed up.
  • Fixed a reference to SO's bra being too large; it isn't necessarily so.
  • After the art room makeout scene, the game will now properly re-assess the player's school schedule.
  • Various stray DIV tags cleaned up.

Version va0-009-hotfix

  • Cock size now prints correctly on the first page. It was not being set until the first transformation.
  • Name and opposite-sex name now print correctly on the Character page as soon as they are set. Nicknames are now included.
  • Variable name error fixed on "shoulderbonus." It was missing the $ (variable indicator).
  • Typo fixed.

Version va0-009

  • Shoulder width should now function properly, with bonuses.
  • A bug with vocal range has been fixed and it should now register properly. It will also change quite a bit faster than before.
  • A bug with height not being calculated correctly has been fixed.
  • A behind-the-scenes feature has been added to skip forward to Day 8 under a variety of different conditions. This is not available to players and is only for testing.
  • Day 11 is now complete.
    • You may proceed after your transformation (if you had one).
    • You can see the results of your Double Secret Transformation (if you did that). Your mom will give you an outfit to match your new sex, and everybody will see you in it.
    • You can talk to the visitor at the school. This is only available (and indeed mandatory) if you have given an open interview to the school newspaper.
    • You must confront the bully after hours. You will have various options for doing so, depending on the choices you've been making.
  • Various fixes to other minor bugs, broken tags, and continuity.

Version va0.008

  • Day 10 is complete.
  • Day 11 is about halfway done. It will end roughly around 4th period or lunch, depending on the path.
  • You can meet your Friend or SO in the hallway after first period for some emergency smooching, but only if you are trying to get back to your starting sex. Your SO may or may not be willing to meet with you, depending how you've treated them.
  • If you do the emergency smooching, you may transform in one of the following classes: Gym, Marching Band, or Pep Squad. Whether or not people notice this transformation depends on your status (if you are in disguise, if you are open, etc).
  • There is a second transformation that can occur on Day 11, with disastrous consequences, but I'll leave you to discover how that occurs.
  • The meeting with your SO on the morning of Day 8 has been slightly refined; there is now a distinct option that occurs if you've never bothered to contact your SO after the first day.
  • Numerous bug fixes and broken tags fixed.
  • New feature: some game choices now provide a super-bonus to a single stat (height, strength, cup/cock, hip/shoulder). They are not labeled by design. These super-bonuses are available at all times — unlike the regular physical bonuses, superbonuses don't care whether you are the correct sex or not. This was added to give players slightly more control, but also to make sure the points kept pace with the pace of the game. In order to deliberately obscure the superbonuses, they will not be reported as part of your regular daily update; instead, they are added in secretly right before you transform.


  • Numerous broken
    tags and italics fixed.
  • Numerous typos and incorrect pronoun variables fixed.
  • Bad story path identifier fixed for reading Shakespeare when teamed with Harold and Ray.


  • Various broken DIV and italics tags repaired.
  • Broken link leading to Marching Band (FTM) has been fixed.
  • Declaring you don't want to kiss boys (or girls) now correctly results in adjusting attraction by -99.
  • Cock size should now print correctly.
  • The sex of the gym teacher has been fixed on Day 8.
  • Dead end has been fixed (don't tell anyone, keep secret from SO and scouts).
  • Day 9 is now completed.
  • Your group reads your scene from "As You Like It" in English class.
  • You will be able to read the results of your newspaper interview and discuss it with your Friend.
  • You will overhear students discussing the article in class.
  • Mom will buy a purse or a wallet (depending on sex), which you can accept for bonus points or reject.
  • Day 10 ticks over, but has no content.



  • Fixed some continuity errors in newspaper interview.
  • If you made out with your SO on Day 8 and transformed before school, you may now try to make out with your Friend, hoping to change back.
  • Another bonus-point activity is available in Bookkeeping and Geometry on Day 8.
  • You may now no longer choose to call your Friend to report how your appointment went. You will, however, tell the Friend at lunch.
  • Scene restored: shopping for Scout uniform, provided you are joining the other group and you are flipped to opposite sex. Otherwise, Mom buys the uniform without you.
  • You can now choose an article of clothing to replicate in Home Ec. The article depends on what you're wearing: what sex you are, whether you went to the Art Room with your SO, etc.
  • Revisions made to the Update routine. It should now be possible to run the day-end Update on a day where you transform, without getting double points.
  • Fixed a problem with the CleanReturn passage. It should now reset to "continue" after a custom link name is used, even if the custom link isn't clicked.
  • Completed Day 8.
  • Day 9 has begun.


  • Added additional footnotes for hot dogs, homework, and the nature of education in the 1940s.
  • Fixed missing parenthesis during doctor's visit.
  • Fixed date alignment. The correct date was not printing on Cycle 0 every morning.
  • Corrected the Schedule Selection code, which would produce the wrong school schedule under some conditions.
  • Corrected Day 7 phone call ("news about appointment") with SO to include results from your date with SO or with Friend, if this was not already communicated on Day 5.
  • Removed the scenes where you shop for a new scout uniform, as they were interfering with another scene. They will be replaced to occur at a more convenient moment.
  • Corrected the flow of Day 6 so it is possible to work on the fence (or on housework) and get your bonus.
  • Added more player choices (how to inform Dot; how to comfort Dot; bathing again) that add more bonus points after Day 6.
  • Full bonus points should now be available on some activities that were incorrectly granting 0 bonus.
  • Upon meeting your SO on Day 8 before school, your SO is happy to see you. You may initiate another transformation if you are "back to normal."
  • Fixed missing "continue" link during newspaper interview.
  • Various other minor bug fixes.


  • Corrected continuity errors in the Gary and Judith dates.
  • Fixed some broken links (particularly Betty + shaving).
  • Day 7 has been completed (doctor's appointment, tell friend or SO about appointment).
  • You may begin Day 8 with an early-morning transformation and self-exam.
  • Transformation self-exam on Day 5 has been modified to better fit the new shape tracking system and bonus points.
  • Added a positive SO response in Marching Band and Pep Squad to include when you have phoned your SO and confessed your condition, but you have not made a date with anyone. The negative SO response should only happen when you have not called at all.
  • Fixed some repeating text in the Bully dialogue on Day 4.


  • Repair of various broken links and tags
  • Some mandatory events have been turned into choices. These choices will add bonus points to various body dimensions as you transform. Some of these activities are noted during the points update, but not all of them.
  • The points summary now states that accumulated Masc/Fem points will only affect you after your next transformation.
  • Day 6 has been completed (scout meeting, working on the fence [if you skipped scouts], contacting your SO [if you had a date with your friend]).
  • Revision of Character page to show body-region bonus points.
  • Fixed a numbering error on the Cast List page and added a few more cast descriptions.
  • Added "dark" mode and revised color scheme of "light" mode. There is now a place to choose initial settings and test the various game color schemes to see which you prefer.


Initial upload.

Total Games: 1,771
Total Contests: 32
Total Reviews: 17,178
Total Engines: 33
Total Adult Themes: 10
Total Transformation Themes: 26
Total Multimedia Themes: 9
Total Online Plays: 3,222,970

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