A self-aligned player is a player who belongs to a faction of size 1, i.e. they don't win with any other player. Most commonly, a self-aligned player will win only if they're the last player alive, causing everyone else to lose; if the player has a "factional" kill, this is known as a Serial Killer, and is by far the most common form of self-aligned role. Sometimes self-aligned roles have been seen that are capable of winning alongside another faction, e.g. Survivor.