Most Common Letter

Find the most common letter in a list of words, using one formula, no helper columns

[@excelchamps]

Thanks Bob. So Smooth.

[@rickrothstein3681]

A proposed change to your formula so that it will be able to report multiple letters when there are ties as to their counts (my guess is there is probably a more compact way to do this, however)...
=LET(x,TEXTJOIN("",,B4:B23),TEXTJOIN(", ",,SORT(CHAR(MODE.MULT(CODE(MID(x,SEQUENCE(LEN(x)),1)))))))