Power of Reverse Polish Notation
text="qxblnsC4566756C60223A30235471636B60286F6C646370247865602B65697E202445636F6\
46560247F6023757363656564602F2F20277573756D616E60bs]xblns/001nlP%001nla=0nl[as]q[i61"
awk -v text="$text" '
BEGIN {
for (i = length(text); i != 0; i--)
printf substr(text, i, 1)
}
' | dc -e '
[pq]sq
[?z0=q ldxq]sZ
[Z1-sZ;dx ldxq Z0<mZ]s?
[ldxqZ1=m ldxq]sf ?
'