Some Role creation and Balancing Insights
Well to start with, since this a setup where everybody makes their own role and alignment, there is no way for us to determine which roles are needed and which aren't. For example you could end up with 6 town vigs but no doctors or cops (totally could see that happening lmao). This would be up to the host to determine and notify us if certain abilities should be removed or added, but from our perspective, we should try to balance our role to perform duties as follows depending on the alignment. Passives will be covered at the end.
Town Roles:
A 20 player game should have roughly about:
2 doctor/protection roles,
1 cop role (Alignment cop)
2 watchers/trackers. (maybe a messager or a 1 shot mason, but not required)
2 roleblockers,
1 vig (or 2 conditional night/even vigs),
2 vote manipulators (prefer to not give town lynch stoppers)
1 redirector/bus driver
1 rolecrusher/equalizer (used to conditionally break super bullet proofs or Godfather/SK immunities)
1 shot anti-janitor (could be incorporated in another role, has a 1 shot that reveals a janitored player role)
This already takes care of about 14 out of 20 players. (town size).
When you are creating a town role, make sure you make it clear which of the above categories you are covering. Say a character like town Itachi could work as a roleblocker with his Tsukuyomi, and also a tracker with Sharingan. Conditionally he could also protect himself or someone else with Susano or rolecrush someone with Sword of Tutsuka.
Try to not go overboard and break a character by making him do more than 3 categories at will. If you are giving someone 3 categories make sure there is some sort of twist to limit how he can use these categories. For example in the case of Itachi, you could make it such that when he activates Susano he is able to protect and rolecrush, but loses his tracker and roleblock abilities. For other characters you can make them cycle between their abilities or simply give them a 1 shot from each category, but try to not go above 4 categories at all costs or else your town character becomes super over loaded for this game size.
Other than that, town should have a couple (1 or 2) town leader characters that are treated as powerful or super roles granting them the ability to pierce through most defenses and preventing them from being permanently amputated or rolecrushed (immune to being permanently vanilla'ed). If they have bulletproofs, it should only be 1 or 2 shots. Who gets to be a power or super role should be up to the host to decide.
Mafia Roles:
A 20 player game should have roughly about:
1 mafia godfather
1 mafia rolecop
1 mafia bus driver/redirector/blinder
1 mafia support (limited shots janitor/doctor/kill amplifier/vote stealer)
This should take care of 4 out of 20 players and will be harder to balance since you have no idea what other roles did other players create, so try your best with the help of the host to develop a solid primary category for you (ex: role cop) but then also have limited shots from one other category and maybe a conditional shot for even another category.
An example of scum Itachi here would be to give his Sharingan a rolecop, which would also allow him take control of that player the following night. You could also make his Susano a 1 shot ability that houses all his scummates inside of it and protects them for one cycle. And if you wanna get creative you can incorporate Izanami within certain limits to delay a player's actions by a cycle or make their actions target themselves, etc... You get the idea.
A godfather should always have some sort of bullet proof vest and a way to fool alignment cops and scan innocent under investigations. Meanwhile role/ability cops should naturally fail on them but trackers and watchers should still work. Mason could or could not work as the host wishes. A godfather could also have a conditional boost ability if 1 or 2 of his scummates die. Such ability could maybe allow him to perform conditional super-kills, or allow him to take control of the night once, or even permanently role crush a player. When scum only have 1 player alive, that player's kills should all become super kills or atleast destroy the enemy's defenses per shot. This is to allow the last mafia to not be permanenly stalled by a bulletproof target.
Scum bus driver should have an unlimited shots night ability that allows him to bus drive 2 targets for a cycle. There should only be one of these per scum team, however there could be a blind ability that would make your target's actions redirect to random. A mafia support could have 1 shot janitor kill, 1 shot janitor lynch, and maybe a 1 shot amp kill, making one of his scummates get access to super kill for a night. Could also have an unlimited shots night protect ability if his other scummates don't have it, and could get access to vote stealing/manipulating ability that could reduce a town player vote power by 1 for example or doubles one of his scummates vote power. Some of these abilities could even be usable at multiple targets at once within host limits. Avoid adding a lynch stopper or make it a conditional 1 shot if you really want to add one. Maybe only stops a lynch when a player only has 4 votes or less on him but doesn't work if they have more than 4 votes. You get the idea.
Either way when designing a scum role, make sure you choose a primary defining category for your character and give your self unlimited shots in that category. (ex: unlimited role cop, bus drives, protects, blinds, or vote manipulation ability). But please try to maintain yourself to 1 unlimited shot ability per scum role. The other abilities can be from the other categories as outlined and can have 1 to 3 shots as needed. You could really be as creative as you want within host limits of course. If you feel your role does too much, consider adding a twist or conditions to limit your abilities.
Independent Roles:
A 20 player game should have roughly about:
1 non-hostile independent (head hunter, or anti specific mafia role ex: anti-godfather, or simply a survivor, etc..)
1 hostile independent (serial killer or arsonist)
0~1 jester
This takes care of the last 2 players (MAYBE 3 but that's a bit of a stretch for a 20 player games). Each independent is treated very differently from the other but they do have one thing in common, they work alone and have their own solo goal. They could buddy with other players as needed to achieve that goal.
Non-Hostile Independents: When designing a non-hostile independent, first start by determining what is your win con and what are you trying to achieve here. Is it to kill a specific mafia role? or survive till the end? or is it to head hunt or protect a specific target.
When creating an anti-mafia or anti-godfather role make sure to give them a 1 shot ability to find clues about the godfather, and/or 1 shot super-kill that only works vs the godfather or which ever role they are supposed to kill. They could occasionally have trackers/watchers and a 1 shot bulletproof.
A head hunter is a non-hostile indie that is given a target by the host at the start of the game and it is their duty to get that target lynched to win the game, regardless of that target's alignment. If that target survives till the end of the game the head hunter loses, and if that target dies in any other way (other than lynch) then the head hunter simply becomes a regular townie and wins by eliminating all mafia. When designing a head hunter make sure to give him some sort of tracker/watcher abilities or messaging abilities to try their best and get their target lynched. You do not need kill shots on a head hunter, and you may need a 1 shot bulletproof, and a conditional super-bulletproof that only works vs your lynch target.
A survivor is a non-hostile independent that has to survive till the end of the game and can win with both town or mafia. This role should typically be given 1 shot bullet proof, and a 1 shot ability to hide behind a player or redirect abilities from yourself to someone else. They can also be given a messaging ability and they have the freedom to take the risk and claim survivor as they like. To make the role more interesting, it is also recommended to add incentive for others to kill the survivor. For example you can reward your killer with a 1 shot super-kill or a 1 shot super-bulletproof. This reward should be announced by the host to the thread.
Hostile Independents: When designing a hostile independent, you should first identify what kind of hostile you are. A serial killer (SK) or an arsonist kind. Serial killers have consistent regular night kills and occasionally possess a super-kill. Arsonists do take their time first and set up the field then perform a double of triple kill all at once.
Regardless of which type of hostile you are designing. You need to have the same protections as a mafia godfather (a bulletproof vest and scan innocent to alignment cops. Role/Ability cops or masons could fail or work on you as the host wishes. Watchers and Trackers should almost always work though.
Other than that, a hostile independent should always have methods to not be stalled infinitely by a bulletproof target. This could be fixed by making it such that if you fail a kill on a target, you will crush their armor for next cycle or permanently. This way the hostile independent can kill any role in the game with at most 2 shots. The hostile independent could occasionally also be granted access to a 1 shot janitor kill, or 1 shot day kill, or 1 shot convoluted double kill or 1 shot super-kill. These could all be conditional and balanced accordingly, or simply only available after day 3 or so on.
Remember that as the hostile independent, you do not need to wipe out all the players by yourself. In reality you will only kill about 4 players the entire game if you are to win, and you are bound to fail some kills. So just cool yourself off and do not create a mass murder role. Bunch of simple consistent or set up kills should do more than enough.
Jesters: These are roles that win when they get lynched. You really do not need any day or night abilities for this one but you can have fun with some trackers/watchers or messaging abilities. Just come and troll on the thread and hope you are lynched. However, the host should make sure to notify the players that a jester exists in the game before hand.
Passives:
Passives are much stronger than active abilities since they are always on without you needing to do anything about them. For town roles, only the super roles should really have access to 1 shot bulletproofs. Maybe at most 2 town roles should be allowed to have that, a super role and a body guard role. For mafia only the godfather has one and it could be limited or infinite shots that block the first lethal ability each night. A survivor could be allowed access to 1 shot bulletproof and a hostile independent follows similarly to the godfather more or less.
Some other common passives are ones that makes your abilities immune to roleblocks, or make you immune to redirections, blinds or bus drives, or make your abilities break your target's protections. Some passives are also targeted toward making you immune to role/ability cops or scan innocent to alignment cops, or prevent your character from being controlled by other players. Some other passives also give you +1 vote power or are a combination of 2 or more passives mashed together.
Other occasional passives could include some sort of a charge system that your characters abilities rely on. Something like souls collected per player dead, or charges that you use to protect other players with, or number of people you investigate or put gas on, etc... These would probably interact with your other active abilities so you need to do a guesstimate in your head and figure out how much of these charges would you roughly obtain per cycle, and how much would that affect your ability usage. If you find you can use your charges too much consider making them harder to obtain or increase their costs.
Final Thoughts:
There is really no right or wrong way to make your roles, specially in a game where you do not see the other roles other players make. Just have fun and be creative with it, however try to stay within limits and boundaries to keep a healthy gameplay and stop too much chaos with 6 vigs running around lol.
