The English version of this card is included in the 2011 Exclusive Warehouse 23 Munchkin Booster and is not a promotional item.
The card is a spoof about John Kovalic, the artist for the vast majority of Munchkin games. The English version calls him a "sketchy character", which is a double entendre referring to his artwork as well as his dubious character. The English-language bad stuff is an "art attack", which is a spoof of heart attack that once again refers to his work as an artist. Unfortunately the word-based humor doesn't translate well into German--the bad stuff, for instance, just specifies a heart attack.
A rough English translation of the card is as follows:
| John of the Dead
Level 13, Undead
+ 3 against Smart Zombies, who have never seen such an unelaborated character.
Bad Stuff: You suffer a heart attack. You're dead