Ѡ is a greek letter which is very hard to pronounce by Slavs. It is wide
O but it can't be
ЬО. It was used in Cyrillic but in very rare cases as we can see:
"Omega (Ѡ, ѡ) is a letter used in the early Cyrillic alphabet, descended from the Greek omega (Ω, ω).
Unlike Greek, the Slavic languages had only a single /o/ sound, so omega was little used compared to the ordinary letter on, О о, descended from Greek omicron. In the older ustav writing Omega was used mainly for its numeric value of 800, and rarely appeared even in Greek words. In later semi-ustav manuscripts it was used for decorative purposes, along with a broad version (Ꙍ, ꙍ) as well as a broad on (Ѻ, ѻ).
Modern Church Slavonic has developed strict rules for the use of these letterforms."
http://en.wikipedia.org/wiki/Omega_(Cyrillic)