The berlin rule is "Exploration and discovery". If we remove exploration but keep discovery we are still breaking the rule by not having both. It's a technicality but it keeps the challenge possible so I'll take it.

It could also be twisted more loosely, based on the more specific definition of "The game requires careful exploration of the dungeon levels and discovery of the usage of unidentified items. This has to be done anew every time the player starts a new game."

Unknowns are fine as long as they're not too similar to unidentified potions or random dungeons? Discovering reliable properties or emergent events are still on the table. "Not exploring" a landscape could mean you have a map, or something.

Then again, given that there's no grid and low complexity, there could be no map at all...

maybe even what makes games compelling.

I think the direction I'd take is to just steer clear of the kinds of exploration & discovery that roguelikes exemplify. No resource-limited exploration of nooks & crannies for items. No random items with testable properties. No... item identification in a mechanical sense. But surely no game can survive without discovery, just as no game can survive without complexity.

Wrote this while reading the blog post.

Having come to the end, it was a really good read! The No Berlin Roguelike will probably take form very slowly (well, mine anyway) b/c I'm working on other major stuff... but I have yet more to chew on now.