Maoyuu Maou Yuusha: Kono Monogatari wa, Daniku dake Dewanai no Ja!

This is only a recap episode, it doesn't have to be watched, not pertinent to the story. That being said, I don't think you could watch this as a substitute for episodes 1-9. It leaves out a lot of important information. Some of those concepts are somewhat complicated, and require more than a sentence to fully explain. They leave out some characters in this recap, as well as some plot points. However, the way the did this was interesting. Instead of having a narrator give an overview, they had "storytellers", which was a nice change of pace from usual recap episodes. Brownie points for that.