Obviously any move (starting at a given position) may be a blunder, see Kh3 Ra4 Nf5 - Kh1 Rf2 where both sides may miss a mate in one until kingdom come. It might be amusing to watch two engines programmed to always play the worst possible move, but I'm rather interested in miscalculation in complicated positions.
Thus, with arbitrary numbers inserted: Take a megabase, both players at least 2100 ELO, let "blunder"="engine evaluation changes by at least 3 pawn units" (as with the also near-lying "+ to - or vice versa", changing repeatedly from +0.1 to -0.1 can't be termed blunder). It should be easy to write a program finding the game with the most blunders this way (especially as such blunders will be rare, see the linked question).
