CISRA Puzzle Competition 2008 - Solutions

This is the archive of the 2008 Puzzle Competition. Please visit the current competition site for information about the latest Puzzle Competition.

D.5 Schrödinger's Wolves

You are playing a game of Quantum Werewolf. No prior knowledge of the game is assumed. The rules of the game are implied and suggested in the puzzle text, and the challenge is to gather a good enough understanding of them to solve the puzzle. It's not necessary to completely understand how the game works, you just need enough to deduce or guess the steps described below.

In a standard game of Werewolf (also known as Mafia), a minority of the players are werewolves, and the majority are innocent villagers. In Quantum Werewolf, the identity of the werewolves is distributed over all players as an Evil probability. Each player's Evil probability changes over the course of the game. Each night, every player makes an attack, and their victim's resultant Dead probability corresponds to the attacker's Evil probability. When a player dies, their evil probability collapses to 0 or 100%, and this then flows on to affect other players.

Information can be pieced together as the game progresses. Using information up to and including the second table:

  • You know that you are Player 4, and your name is Manuel. So Player 4 must be Manuel.
  • Kieran has died, and Player 7 has a 100% Dead probability, so Player 7 must be Kieran.
  • Players 1 and 4 (each 8% Dead) must have been attacked by Players 1 and 2 (each 8% Evil). Player 1 cannot have attacked himself. Therefore Player 1 attacked Player 4, and Player 2 attacked Player 1.
  • Only Player 5's Evil score of 15% could have caused Player 6's Dead score of 15%, so Player 5 attacked Player 6.
  • Players 2 (23% Dead) and 5 (46% Dead) must have been attacked by Players 3, 4, and 6 (each 23% Evil), with Player 5 the target of two of those attacks. Because Parker died the following evening with two sets of wounds, Player 5 must be Parker.
  • Fabian must have a non-zero Dead score, because you can partly see through him. So Fabian cannot be Player 3, who has not yet been attacked at this stage.

So far you know this much:

PlayerNameTarget in 1st attacks by:
1?Player 2
2?one of 3, 4, and 6
3? (not Fabian)   nobody
4ManuelPlayer 1
5Parkertwo of 3, 4, and 6
6?Player 5
7Kierannobody

Reading further, to the end of the third table, more can be deduced:

  • Apart from Fabian, Player 6 has died, so Player 6 must be Arthur (who was sacrificed).
  • Player 4 (33% Evil) has attacked Player 2 (33% Dead) in the second round of attacks. You are Player 4 and you attacked Santos, so Player 2 must be Santos.
  • Before the second table, Player 6 (Arthur) attacked either Player 2 (who survived the night) or Player 5 (who died, the victim of two attacks). Player 5 (Parker) was found dead from two sets of earlier wounds after (and as a result of) Arthur being revealed as innocent, so Arthur could not have been responsible for one of these two sets of wounds. So in the first attacks Arthur attacked Player 2.
  • All of the attackers in the first set have now been identified, except those of Player 5. By elimination, Player 3 and 4 attacked Player 5 in the first attacks. This matches with the fact that the remaining werewolf can only be Player 3 or 4, since all other living players are 0% Evil.
  • Only Players 1 and 3 are unnamed. One of them is Fabian. But earlier we have deduced from his ghostliness that Fabian cannot be Player 3. So Player 1 must be Fabian.

You now know the following:

PlayerNameTarget in 1st attacks by:
1FabianPlayer 2
2SantosPlayer 6
3?nobody
4Manuel   Player 1
5ParkerPlayer 3 and 4
6ArthurPlayer 5
7Kierannobody

The narrative tells you that the attack targets on the "first day" are significant, which must refer to the first set of attacks. Re-ordering the list of attack targets by their attacker's number gives the following:

PlayerNameTarget in 1st attacks by:
4Manuel   Player 1
1FabianPlayer 2
5ParkerPlayer 3 and 4
6ArthurPlayer 5
2SantosPlayer 6
3??????nobody
7Kierannobody

Now, if we index each name according to their attacker, we spell out the name of Player 3: Markus. Voting to sacrifice Markus ensures your survival, because:

  • If he is revealed to be a werewolf, then all of the remaining villagers, including yourself, will be safe after he's dead.
  • If he is revealed to be a villager, then only you can be the second werewolf. You alone will survive, because once you are revealed as a werewolf, Santos will disappear having died the previous night (like Parker did), leaving only Fabian who you can eat on the coming night unimpeded.

Therefore the solution is MARKUS.