Bastard Mod, usually shortened to Bastard, can ambiguously refer to a type of role, a type of game, or a mod who runs bastard games and/or uses bastard roles.
The exact definition of "bastard" varies from person to person according to their likes and dislikes; however, the following traits are usually common.
- The moderator lies to players, either in their Role PMs (as in False roles) or in their revealed information (as in Death Miller).
- The game incorporates significant game-changing mechanics (Cult being a notorious example) that affects players who may not know about them.
- The game incorporates roles that are inconvenient to play with, such as Voteless or Doomed.
A common shorthand definition of a bastard mod game is that it is designed mostly for the moderator's amusement more than that of the players.
Bastard games are notoriously difficult to do well. Most moderators' bastard setups will be imbalanced or not fun for some other reason. This doesn't stop them many moderators from trying to run them, though.
Bastard Mod games should not be confused with bad games, which are self-explanatory. However, the line between the two tends to be dangerously thin. If players called your game "bastard" when you were not actively trying to make it one, you should consider getting your next setup looked over by better reviewers.
On mafiascum.net, several Queue threads require a game with any of the mechanics in the list below to be labelled as "bastard":
- mid-game alignment changes
- moderator lies that cannot be reasonably anticipated (for example, Godfather, Tailor, Miller, Ninja, and mechanics like that are generally fine, but telling someone they are a Reflexive Doctor when they're actually a Paranoid Gun Owner is not)
- secret win conditions
- un-divulged non-randomness in player role/alignment generation
- direct moderator influence during the game
This is best seen as a list of mechanics that are both a) commonly seen as bastard, and b) sufficiently commonly used in games to need a rule against them. (There are some mechanics, such as Jesters, which are considered to be bastard by many players despite not appearing on this list, but moderators rarely place Jesters in non-Open games and thus players are normally forewarned in that situation.)