Via David Breitenbeck, here’s a list, “Things Mr. Welch Is No Longer Allowed to Do in an RPG.” A few items from the list:
20. Polka is not appropriate marching music.
94. I cannot base my ancient kung fu master on either Gene Simmons or Bluto Blutarski.
105. I am not allowed to polymorph anyone into Abe Vigoda.
134. The King’s Guards’ official name is not “The Royal Order of the Red Shirt”
174. There is no use of Shatner’s spoken word album that doesn’t require a humanity check.
199. My third wish cannot be ‘I wish you wouldn’t grant this wish.’
221. If I get that Yugo up to 120mph again, that’s gonna get some paradox.
251. I am not the Boogie-Woogie Bugle Boy of Gundam Wing Z.
289. My character does not have the flaw Addiction: Helium.
330. The Halfling Paladin does not represent the Lollipop Guild.
411. It is bad form to shoot a god while he’s monologuing.
476. The alignment of 2 years olds is not automatically Neutral Evil.
559. Even if the Ranger offers his sword, the elf his bow and the dwarf his axe, my gnome can’t offer his accordion.
623. Even if the rules allow it, I cannot play a Dire Gummi Bear.
651. My alignment is not Sarcastic Good.
753. No encouraging Swedish accents.
781. My tribe’s trial by combat ritual is not best described as “Calvinball with axes.”
845. It’s not a good idea to taunt Greek heroes with “Who’s your daddy?”
968. A paladin with a British accent is acceptable. One with a Peter Lorre accent isn’t.
975. There is something wrong with a 2nd level Kamikaze.
1172. My brooding costumed vigilante can’t take the flaw Dark Secret: Well Adjusted to Society.
1337. Can’t lure the Bastet into an ambush by turning on the can opener.
See also DM of the Rings and Chainmail Bikini.