the key: 5 1 4 2 3

stage 1

A D V A N
C E T H E
A T T A C
K T H R E
E H O U R
S X X X X

DETTHX AHARUX NECERX VTTHOX ACAKES

stage 2

D E T T H
X A H A R
U X N E C
E R X V T
T H O X A
C A K E S

EAXRHA TAEVXE HRCTAS THNXOK DXUETC