Behold the MAGICAL GROWING ROD! *ZOOM* Watch as it grows at one tile per cycle!
And with a flick of the wrist: *WHOOSH* See how it transforms from Gold to Silver! Now selling at the low, low price of 705 G!

(Disclaimer: MAGICAL GROWING RODS are one time use. No refunds.)

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(PS ignore if 20 is min cycles)

Mere hours before the deadline, I was struck by a vision of a "REVERSE MAGICAL GROWING ROD" that turned from Silver to Gold! Building the silver rod first allows you to validate while the last input is still processing. Using the dark sorcery of half cycle projection, a newly GOLDEN rod could move onto the output on cycle 19! BLASPHEMY! IMPOSSIBLE!