A modest improvement on your 229:
227 strokes

perl -E'@x="033544355436688779880066555766"=~/./g;$_=<>;chop;print;whi
+le($_-4){split//,"99aabb87780";$x=4*!$_;$x+=hex(pop@_)*!!-$&+!!$1*($x
+[$1]+7)+$x[$2+20]+$x[$3]while s/(.??)([^1]?)(1?.)$//;say" is $x.";pri
+nt$_=$x}say" is magic."'

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In reply to Re^2: Code Golf: Four is magic by thundergnat
in thread Code Golf: Four is magic by deMize

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