0. There's no God. If you die, you report your own death and are responsible for answering investigations on it. (Once someone dies who feels like helping with God-related stuff, they're welcome to.)
1. Everyone RNGs their own role with an online RNG. You have probability p of being a serial killer. Independently, you have probability p of being an investigator.
2. Investigators (who may also be serial killers) RNG each day whether they have an investigation, with probability q. If they do, they may PM one dead player that day (whose death they have not already investigated) and ask them whether one other player killed them, and get an honest answer.
3. Serial Killers RNG each day whether they have a kill, with probability q. If they do, they may kill a player (normal bang mechanics). If a serial killer attempts to kill another serial killer, then the latter disarms the former and neither dies but the former loses their kill for that day. If a serial killer doesnt use their daily kill, they don't keep it, but they are not otherwise penalized; they RNG afresh the next day.
4. Lynches occur each night at day end by random ballot. Every player submits a vote by posting it on a lynch thread in forums. Each night after submitting votes, one player is provably randomly selected, and the player they voted for is lynched. Voting No Lynch is an option, and is the default if a player forgets to vote.
5. There are no items.
6. Day 0 is on Sunday. Day 1 is Monday. Kills may be made starting 8:00 on Monday. Thereafter, day rollovers are at 23:00, but day is extended an hour past any kill that happens in the last hour of day.
7. If at any point there are no serial killers alive and at least one non-serial killer alive, game ends and all non-serial killers win and all serial killers lose. If at any point there are no non-serial killers alive, game ends and all non-serial killers lose and all serial killers win.
8. No provable randomness other than that specified in the rules, cryptography, faking incants, or other shenanigans generally outlawed by mafia.
9. Kills cannot be made in Dorm, or on players who are currently driving (defined as being in the driver's seat when the van is not in park OR not in a parking space).
10. p = q = 3/10. To randomize, each player goes to
www.random.org and generates three numbers in the range [0,10^8) and concatenates them, adding leading zeroes if they have less than 8 digits (CHECK YOUR LENGTH!). For example, 209002769825222899384575. They then perform a SHA1 hash on this number at
www.sha1-online.com (this example would get f549925ccfb756cdf2975a2c1696d8c49a6c502d) and post this hash on forums for post-game accountability; nobody will try to break it. Then, town provably randomly generates two random numbers in [0,10), and each person looks at the next 2 numbers in their private number, and adds the public numbers to them mod 10. If the number is 0, 1, 2 it's a yes, otherwise no. The first of these is the serial killer probability and the second is the investigator probability. On day 0 this is the probability of being that role, and for each day thereafter it is the probability of having that ability if they have that role. For example, on day 0 the town RNGs 9 and 4, and the person adds these to their numbers 2 and 0 to get 1 and 4. So they are a serial killer but not an investigator. The next day the town RNGs 7 and 2. The person adds to get 6 and 2. They don't get a kill that day (because 6+9=5 is not 0, 1, or 2) and they don't get an investigation (because 2+0=2 would get an investigation, BUT they're not an investigator). And so on. Town RNGs the numbers for a day 24 hours before the day will start.