**Full solution is found at** https://github.com/happysox/CTF_Writeups/tree/master/InCTF_2018/load3r
```
def decrypt(cipher, key):
#Reverse the string and xor with 5. Bitshift left or right based on key.
plaintext = ""
for char, bit in zip(cipher[::-1], key):
if int(bit):
plaintext += chr((ord(char)^5) >> 1)
else:
plaintext += chr((ord(char)^5) << 1)

return plaintext

cipher = "w2g1kS

Original writeup (https://github.com/happysox/CTF_Writeups/tree/master/InCTF_2018/load3r).