@avdg_: Yeah, I figured that out lol. I just used .lookAt if it returned a pos value, but as the bug is fixed it's no big deal.

Aw man, code broke 3h ago because of this. Are we expected to start using .lookForAt calls or something?

See this post; it looks like this deals with the same issue.

I'd like the amount of time for a room to degrade to be based on progress rather than ticksToDegrade. Maybe, every tick, the progress of a room controller is removed by the RCL (or just 1, if that's simpler), then you can still send creeps to attack controllers to speed up the process.

Also, I find that there are a lot of rooms with a single spawn that are completely inactive. Perhaps this degradation could come into effect when there are none of the owner's creeps in the room?

Yeah, I've seen that post before. I really don't like it since it's quite counter-intuitive compared to the rest of the health & part mechanics (creeps should always get weaker as their hit points deplete), so it's just an oversight in my book.

From what I've seen, a part sometimes (always?) maintains full functionality until all instances of it are destroyed; a creep with ATTACK parts will be able to attack at full force until his opponent disables all his red parts.

Can confirm, not sure what's wrong with it. Maybe it has to do with a room not having either sources or a controller? I don't think I've seen any rooms like that anywhere else.

Yep, everything's working just fine now. Awesome!

The changelog released earlier today appears to have made construction sites count as the structures of their type (e.g. it's now "impossible" to have 20 construction sites for extensions when your RCL is only 3). This change makes creating a new spawn inside an empty room which you have claimed impossible.

From what I can see, this is caused by some sort of check before completing a construction site which will reject completion if the amount of structures is beyond the current limit. Since that check is instead done before a construction site is even created, this final check could probably be eliminated entirely or at least updated.

Basically, creating the final spawn, extension, link, etc. you can currently build at your RCL is impossible; Creep.build will just return -14.

From what I can see, W9N5 was sending your ranged attacker creeps to both W9N4 and W8N4; I'm guessing it has something to do with your script having an allergic reaction to non-keeper lair hostile structures in a room.