- Nobody Dies, an Evangelion fanfic, quotes Xykon in chapter 21.
Yui: This is your Idiot Tax. This is the price you pay for having a quickie in the broom closet when you are supposed to be watching the Children and your Daughter.
- As part of a communications test in Harry Potter and the Methods of Rationality, Draco sends Harry the message "beware of the green monkey," specifically mentioning it was Spy Speak in a play he saw once.
- Dungeons & Dragons provides a subtle one in the 3.5 Dungeonscape supplement, where you can buy a bouncy ball... just like the one Xykon inscribed a symbol of insanity on. Rich Burlew was one of the authors.
- Darths & Droids directly mentions Xykon in strip 676, putting him on the same level of Obviously Evil as Darth Vader.
- One "critical missives" from Rusty and Co. features the Princess in the OotS-stick figure style.
- Yet Another Fantasy Gamer Comic as a full-strip homage copying both the style and page layout of OotS.
- In Girl Genius, among many, many signs referencing other webcomics, we have:
BURLEW's RESTAURANT. Try an Order of the Stick with our famous pie!
- Goblins: One of the filler pages consisted of a very crudely drawn stick-figure comic that was drawn in-universe by Fumbles. One of the other goblins reading the strip felt like he'd seen a stick-figure comic set in a universe which adhered to Dungeons & Dragons rules somewhere before.
- The Goblins spin-off Tempts Fate has The Rant Golem, which Lampshades and complains about several things wrong with the comic, before concluding "Order of the Stick is better."
- At the 2012 Halloween party on The Whiteboard, Gino dressed up as Roy Greenhilt.