SOLUTION - Logic Puzzle: For the Watch

1.	Each corner contains a commander of a Night’s Watch tower active during ‘A Storm of Swords.’ The only four commanders during that book were Jeor Mormont, Lord Commander at Castle Black, his successor, Jon Snow (already accounted for), Denys Mallister, Commander of Shadow Tower, and Cotter Pyke, Commander of Eastwatch. Therefore, these four characters must inhabit the four corner spots. Since Jon shares a diagonal with his predecessor, Jeor Mormont must be in the opposite corner, E5.

2.	The fifth row contains Black Brothers born into noble houses, so the corner space A5 must contain a commander from a noble house. Cotter Pyke is a bastard and doesn’t fit the bill, so Denys of House Mallister must go in A5. By necessity, this puts Cotter Pyke in E1.

3.	Denys tells us the first character in the series to die is in his row. That character would be Waymar Royce—any ambiguity about whether becoming a wight is ‘dying’ is unimportant because to be in the bottom row, a character must be in a noble house, and the first character to die a definitive death is Gared, and he isn’t nobility. Cotter’s clue says all three of the first characters introduced (Waymar, Will, and Gared) are in Column C. Therefore, Waymar Royce is in C5. Denys also tells us that all four POV characters from the Watch are in the quiz. For future reference, these four characters are Jon Snow, Sam Tarly, Will (AGoT Prologue) and Chett (ASoS prologue).

4.	After Waymar became a wight, he killed Will. According to his clue, he must be adjacent to Will, and according to Cotter, Will is in Column C, so Will must go in C4.

5.	The two characters left in row 5 were born with surnames that begin with the same first three letters, one of whom is a maester. These two characters are Maester Aemon (Targaryen) and Sam Tarly. Since Column D contains only living characters, Sam must go in D5, which leaves B5 for Aemon.

6.	The Old Bear (Jeor) is adjacent to his killer. There are two empty spaces adjacent to Jeor, but Will told us everyone in Column D is alive. Jeor’s killer, Ollo Lophand, was murdered by Coldhands, so he can’t be in D4. Therefore, he must be in E4.

7.	Ollo shares a diagonal with Old Pomegranate (Bowen Marsh). He also says the three spots adjacent to him on his left contain a ‘monkey,’ an ‘aurochs,’ and a ‘piggy.’ Sam was nicknamed Ser Piggy by Alliser Thorne, while Pyp was called monkey and Grenn was aurochs. While we can’t say for sure which space is Grenn’s and which is Pyp’s, we know that Bowen Marsh must be in B1, C2, or D3 to share Ollo’s diagonal. Either Pyp or Grenn inhabit D3, and everyone in Column C is dead. So Bowen must be in B1 (as he also fits Waymar’s criteria of killing or being killed by Jon Snow).

8.	If Grenn inhabits either D3 or D4, he isn't adjacent to Jon. So to be adjacent to three POV characters, he must be adjacent to Sam, Will, and Chett. Chett is not yet placed, but D3 isn’t adjacent to Sam, so Grenn must be in D4, which puts Pyp in D3.

9.	Back to Sam’s clue. Sam shares a diagonal with Dareon (who he punched in Braavos). His only two remaining diagonal spaces are A2 and B3. Neither Jon nor Dareon killed the other, so Dareon can’t be adjacent to Jon. Therefore, Dareon is in B3.

10.	There are three characters in the quiz we’ve seen at Winterfell, according to Dareon, and they all share a column. Jon Snow was seen at Winterfell, so the other two must also occupy Column A. Pyp’s clue tells us Mance Rayder is in the quiz, and he appeared in Winterfell (once as a bard during King Robert’s visit, and again as Abel the Bard during ‘A Dance with Dragons’). Grenn’s clue says Benjen is in the puzzle, and he was also seen at Winterfell during the feast with King Robert. Jon did not kill either of them, nor did they kill him, so Mance and Benjen must be in A3 and A4 (in some order). But Grenn’s clue also says the character to Benjen’s right can’t go south of the Wall. There is a character who dresses as a brother of the Watch who is bound to the North of the Wall by magic—Coldhands. Since the spot to the right of A3 already contains Dareon, Benjen must be in A4, with Coldhands in B4 and Mance in A3.

11.	Now we can look at Maester Aemon’s clue. He says he shares a diagonal with the only character known for CERTAIN to be older than him. (While Coldhands could very well be older than Aemon, his age and origins are unknown.) There is only one character in the series associated with the Night’s Watch who is known to be older than Aemon, who was 102 when he died: Bloodraven, or Brynden Rivers, one of Aegon IV’s Great Bastards and former Lord Commander of the Watch. Pyp’s clue confirms that Bloodraven is in the quiz, so Brynden must go in E2.

12.	Coldhands’ clue says Iron Emmett is directly between Cotter Pyke and the ‘kennelmaster,’ who we know as Chett. We know where Cotter is, so for Emmett to go between him and Chett, Chett must be located in E3, C3, or C1. We can rule out E3, since Bloodraven is in E2, where Emmett would go if that were Chett’s spot. This puts Chett and Emmett at C1 and D1, respectively, or C3 and D2. Looking back to Bowen’s clue, we recall Grenn must be adjacent to three POV characters. Therefore, Chett is in C3 and Iron Emmett is in D2.

13.	A2 had his head chopped off. The fates of Jon’s killers remain unknown, so we can assume A2 was beheaded by Jon. It must be Janos Slynt!

14.	Mance’s clue says the top row contains a deserter who was caught and beheaded. This character can’t be in Column D, since everyone there is alive, so he must be in C1. The last two characters in Column C are Gared (per Cotter’s clue) and Small Paul (per Chett’s clue). Small Paul was killed by Others, but Gared deserted after the events of the AGoT prologue and was beheaded by Ned Stark. Gared is in C1 and Paul is in C2.

15.	Gared has two open spaces in his diagonals: B2 and E3. One of these contains Alliser Thorne. Last we saw of Thorne, he went Beyond the Wall at Jon’s command, so he can’t be in a space adjacent to him. That puts him in E3.

16.	There are two spaces left. Pyp’s clue tells us Qhorin Halfhand must turn up in the quiz. Qhorin is dead, so he can’t go in D1, and he was killed by Jon Snow, so he qualifies to be put in B2.

17.	Qhorin’s clue tells us the identity of the last Black Brother, who goes in D1: Dolorous Eddison Tollett.