Because i see a lot of people struggling, here's the answers to the demon, the angel, and the bird puzzles.
Code is Vigenere, Key word is Key
Iss mel qir rmldw dbsk dlc zvgcslov gx xfo accx ayypd.
Xfo tpswmxip cewc 36 Hcfmjc ml yrc yj rri fsrrc. Gmxzcbx 36 gxxm leqo 2 (RMD fgxepi gmni, zkwc 2) krb iss qir yr mpj mpj mx sdp sdp
Tpswmxip cewc 13 Elqijc. Gmxzcbx ry fyci 2 yxh wyy eox mpj mpj mx sl yjd yr
Nbmqyrcb wyiw 20 qzepbsuc. gmxzcbx ry fyci 2 yxh wyy eox
mpj mx sdp sl yjd yjd