This is one of the reasons I include the view game details option. (if you click the little information icon, you can see everything about his game, including the longer words he made)

It actually IS possible to get that high of a score without "cheating" – by hoarding powerful letters and using them together. (stacking multipliers is really the second level of the game strategy for score)

But, in his case, he did it with 60 (mostly uncommon) eight letter words, and his "strongest word" point-wise is weak, so that's the give away.

Generally I just let the high scores stay and people can sort of figure out which ones are legit and not. If I banned them using an algo it would eventually get much harder to tell so not much point I guess.

This is one of the reasons I use a "only show the scores made in the last week" scoreboard, so the cheat scores don't stick around too long.

-Seth (developer of Dungeon Scroll)