Yellow Flag (Solution)
by Derek Kisman, based on an idea by Amos Eshel
Here is an unordered list of answers to the twenty round puzzles, for reference. The colors identify which puzzle answer this is (e.g. DAMP is the answer to the red/green edge cubelet).
RYB SHLEP RY EXTANT RYG DEDITION RG DAMP RWG BOIL RW UNARY RWB CONTIGUOUS RB BASSIST YB SLAUGHTER YG BEER CHUGGING WG EDITH PIAF WB CREAM OF TARTAR OYB ARMORED RECON OY HYPAPANTE OYG COMMEMORATIVE BATS OG DERRICK TRUCK OWG BROWN ROT OW ATTORNEYS GENERAL OWB SACROSANCT OB IMPROMPTU
At each position 1-9 of these answers (ignoring spaces), a single letter is repeated across two answers (e.g. there are two words that start with S, two that have second letter E, etc). These letters additionally spell out SEMAPHORE. Forming a semaphore flag by the two positions the answers are in (orientation is provided by red being on the ‘north’ side), and reading in the order of SEMAPHORE spells out the answer, WONDERING.
NW DEDITION N EXTANT NE SHLEP E SLAUGHTER SE ARMOREDRECON S HYPAPANTE SW COMMEMORATIVEBATS W BEERCHUGGING
S NE/E W E NW/W O M SE/SW N A N/S D P NE/S E H E/W R O NW/SW I R SE/SW N E SE/S G