Missing Upgrade Disk

[Jaqalyte]

Ok, so after getting my second disk at the Trading Post and being stuck on 15 disks for a while, I looked up a list of the locations and... I'm sure I've collected all of them. Any idea what could be going on? Is there a way to figure out which one I'm missing beyond checking every location again?

[Silyon]

Nope. You're the only one that knows which disks you've collected and which locations you've been to, so the only real option is to go through and double-check each location. I would venture if you're missing any of them, it would be one of the less commonly encountered ones like The Mechanarium or Lost and Found. Especially since the latter's a room you normally don't want to enter.

[Jaqalyte]

After checking a video showing all the locations, I think it might be the one in Her Ladyship's Chamber as that room appears rarely with how I draft and the disk blends in with the desk. Trying to force it in a run to check. If not there, then maybe the freezer? Only unthawed it once... will update when I find it.

[Jaqalyte]

Ok, it's the freezer. I remember picking it up before, but I must have not used it in that run. Duh.

[Vercci ]

You could use the showroom and trading post to force more upgrade disks if you're rich enough.