u/Aromatic_Steamer

I'm playing the GOTY edition of Oblivion from Steaming running on Linux. This comes with DLC Shivering Isles. I get the prompts that a strange door has opened, and the door is marked on my map, but when I go there, I find this. I ignored it originally before I realized this was the gate to the entire quest. I've tried verifying file integrity and it passed the Steam test. Anybody experienced this and know how to solve it?