Try using lots of punctuation variables for short japhs, separate operators from their operands, use funny math to hide constants, take advantage of aliases and default arguments. I like the idea you had on this one, so here it is a little less clearly:

map{$;=1?$?-$?:t;$;=($_*$;+ord$&)%(2**7-$|)
while(qq]%E.g\cle(WW7=k\ct[bqI\abJy3.%\ctG]
=~m>.>g);$..=chr$;}++$|..26;s++$.+iii;print
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Brandan L.