Like it says on the tin.
SLY MARBO has come to Earth during WW2, thanks to the Thule Society trying to open a portal to the Aryan homeland, but opening one to The Warp instead!
Needless to say, to SLY MARBO, Earth is filled with Xenos that just happen to look(and bleed) a lot like him.
So the One Man Army decides to execute the Slowest Exterminatus in the Imperium: DEATH BY SLY MARBO!
Can SLY MARBO defeat WW2 Earth?