Castle Smurfenstein is a Smurf-themed total conversion by Dead Smurf Software, of Silas Warner's Apple II game Castle Wolfenstein, published by Muse Software. It is the first ever game "mod". Homer Simpson makes a reference to this game in the "Medal Of Homer" level of The Simpsons Game. This is the second and the last Smurfs game published by Dead Smurf Software, with the first being "Dino Smurf", a game which is based on the 1983 computer game Dino Eggs by Micro Fun.