With Arneson's influence, Chainmail was adapted to include:
- Exploring dungeons
- Using a neutral judge/dungeon master
- Conversations with imaginary characters (NPCs) to develop the storyline
- Hit points
- Experience points
- The concept of role-playing an individual character rather than just rolling dice
So, basically, he put the "R" in RPG.
While it is not the intention of this blogger to try to undermine the legacy of Gary Gygax (I also dont think that was the point of the Cracked article), it is nice to see Arneson get the credit he deserves.