# Cipher: Find the murderer

Bob was killed by someone.

This is what you found at the crime scene:

the person who ended bob's life is Iapes Ehzn

also, the person is Ictlb Puod

Jolin Hera

Rivka Mond

Hyman Yarn

Chari Davi

Ellis Chan

• What are the names listed below the quoted text? The possible suspects? Also, why the [optimization] tag? – Rand al'Thor Oct 12 '16 at 13:16
• yes, and I was looking for a mystery tag, but I misclicked. – garr890354839 Oct 13 '16 at 5:12

The murderer is

Hyman Yarn

because

if you move the $n$th letter in "Hyman Yarn" ahead by $n$ places in the alphabet (wrapping round from Z to A if necessary), you get "Iapes Ehzn". At least, this works for all but the last letter - possibly the OP made a mistake with that one?

Check:

H -> I
Y -> Z -> A
M -> N,O -> P
A -> B,C,D -> E
N -> O,P,Q,R -> S
Y -> Z,A,B,C,D -> E
A -> B,C,D,E,F,G -> H
R -> S,T,U,V,W,X,Y -> Z
N -> N (?)

Thanks to mr23ceec, "Ictlb Puod" also fits the same person because

if you move the $n$th letter in "Hyman Yarn" ahead by $3n-2$ places in the alphabet, you get "Ictlb Puod", with some letters out by exactly one place (maybe the OP miscounted?) and again the last letter not quite working.

Check:

H -> I
Y -> Z,A,B -> C
M -> N,O,P,Q,R,S -> T
A -> B,C,D,E,F,G,H,I,J -> K L
N -> O,P,Q,R,S,T,U,V,W,X,Y,Z -> A B
Y -> Z,A,B,C,D,E,F,G,H,I,J,K,L,M,N -> O P
A -> B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S -> T U
R -> S,T,U,V,W,X,Y,Z,A,B,C,D,E,F,G,H,I,J,K,L,M -> N O
N -> D?

• There was probably a BMYguest puzzle with some circles which probably used same encryption. – user27395 Oct 12 '16 at 13:27
• By the same token, Ictlb Puod is [That person] starting at -1, with step -3. – mr23ceec Oct 12 '16 at 14:25
• @mr23ceec Well, almost ... – Rand al'Thor Oct 12 '16 at 14:36
• That's what I got for Ictlb Puod but threw it out coz it didn't quite work out. There's sort of a pattern. – n00dles Oct 12 '16 at 14:42