Atari Dragon

From Homestar Runner Wiki

A 4-bit creature that at first glance looks like a duck. But if you look closer, well, it still looks like a duck. It seriously is a dragon, though! It personifies ((Fhqwhgads)) in everybody to the limit and also appears in Main Page 13, where Strong Bad confuses it for a duck.

The dragon comes from the ATARI 2600 game Adventure. The object of the game Adventure was to take a magic chalice and place it in the starting castle (Strong Bad is carrying this Chalice in Main Page 13). The three dragons in the actual game were yellow, green, and red, meaning while the yellow dragon in the mainpage could be considered an actual character from the game (Yorgle), the white dragons in Everybody to the Limit are not.

Adventure is significant in video game history because it contained the first Easter Egg; because game programmers back then often worked alone and received no credit for their work, Adventure creator Warren Robinnett included an almost impossible-to-reach room with his name posted in it. More information can be found on Warren Robinett's webpage.

A playable flash version of Adventure can be found here, although it doesn't have the difficulty levels, it's a bit clunkier, the items are all in different places, and it has the red dragon on difficulty level 1 where the original game didn't. It's still close enough to give an impression of what the game was like, though.