However twenty-six is not a recognised hyphenated term. IMO, we should reject such hyphenated words as it is basically leads to "cheating" to get rarer letters.
We have (long ago) accepted use of apostrophes as one word although technically it depends on usage in strict grammar e.g. Didn't is technically two words.
The strict rule (afaik) is if word is a contraction i.e. didn"t means did not. However in possessive e.g. Kim's - harder to define as it means belonging to Kim i.e. Kim his/hers. But we never say Kim his/hers so Kim's is really treated as one word
Proper nouns like Xerox, Biro, Hoover are another grey area but if it it is a commonly used one where they are used colloquially to mean photocopier, pen, vacuum cleaner, then no issue.
Names are fine of course.
In the end, use of lesser well known proper nouns is generally acceptable but I personally think some common sense should prevail e.g. if a company is called ABCD, then that would be unacceptable.
So generally anything goes but let's not generally accept hyphenated words unless it is a (rare) truly hyphentated term never used in an unhyphenatd form as never used before.
In the end, this is a simple game FOR FUN, so let's not get hung up on such pedantic details but use COMMON SENSE.
Anyway carrying on from previous letters repeated here by
@Edwin
RSSDR
