Although more than three years have passed since Painkiller first shot up hard drives, this deeply unfashionable shooter series hasn't done any growing up since 2004. And thank the gods for that. Not too many developers are bothering with old-school shooters anymore, so it's a real pleasure to blast through such a gleefully stupid stand-alone expansion pack like Painkiller: Overdose. All of the design attributes that made the original game as subtle as blunt-force trauma are back for more, including monsters that seem to have escaped from an Iron Maiden album cover, as well as slice-and-dice weapons that wouldn't be out of place in a torture chamber. Only some technical difficulties and the nagging sense of déjà vu interfere with the bloody good time on offer here.