system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] As he is a jedi killing cyborg, why didn't Grevious have an exoskeleton made of more lightsaber-resistant material?
gpt
The only metals that are lightsaber resistant are extremely rare and extremely expensive. The trade federation spent a lot of money building grievous but didn't want to sink more into him. And even without resistant materials in his body his kill count was absurdly high.