I'm not sure about parsing, but it seemed to fit the letter pattern. I'll give it some thought. 'Finished' might fit with the whole word 'endgame', but as for the rest of the word, well, that requires some headscratching.
There is no point in doing an easy crossword all the time - what's the point. You should always strive to go one better. Perhaps this saladdodger's first attempt at The Genius.