The five across clues and answers I have are (in order):-
Bath specialist hotel is monster, but in the end becomes nothing (5) HYDRO
Food - grain - found around church a bit at a time (9) PIECEMEAL
Record by American ... (6) DISCUS
Ornamental napkin holder leads to new English fashion (3) NEO
Spy (mole) with magic disrupted sports festival (7,5) OLYMPICGAMES
Last letter in all provides the template for the final clue.
The setter also states:-
"This puzzle is on a topical theme; also, seven solutions are 21 11 and (unusually) not defined in their clues!
21A is Olympic games
11A is events