In Ultimate Werewolf the Mason cards are a bit abstract on what happens when someone references them. So I would just like to clarify, what happens when more than one person references them. Do they all die? Or do the Masons choose them one by one each night? Also, if there are 2 Masons playing and one Mason references them. Does that Mason die? Or can Masons never die from referencing them. Anyone able to clear this up a bit would be much appreciated. Thanks.
Let me start out by saying I generally don't like rules that restricts what players can discuss. I find that it makes for interesting gameplay to let people discuss freely about what roles exist in the game. - which is why I never play with this "Don't mention the Masons" rule.
That being said, I find that there are 2 reasons behind this restriction:
1. Thematic The masons are a secret society. The masons themselves are not allowed to acknowledge its existance, and the rest of the village simply don't know about it.
2. Balance The Masons may seem somewhat overpowered because they can just tell everyone who they are, and nobody but the evil team has any reason to contest their claim - which allows you to quickly narrow down who's the werewolf.
To answer your question:
Yes, if a mason mentions the masons, they die. If not you could just start the game by yelling "MASON!", and the fact that you didn't die that night would be evidence of your role.
No, the masons don't get to pick and choose who dies. They only wake up the first night to learn each others' identity.
Yes, technically, if everyone talks about the Masons, everyone dies. That'll teach them. After the first massacre people probably won't do it again in future games...
To be honest, the death punishment shouldn't even be needed in my opinion. If the rule is not to talk about the masons, don't talk about the f'ing masons! Just like you're not allowed to look at each others' cards or peak during night time. Obey the rules, or don't play the game.