I remember it. I didn't play it; but I offered some observations [suggested corrections] to the developer, on the day prior to release, last September.
A.H. didn't invent the dungeoncrawler genre, and purposely fashioned Grimrock after Dungeonmaster and Eye of the Beholder. [An homage]
I don't recall seeing this game expressly advertised here during its development or release, but I have seen others do this, and I always wondered how they could...what were they thinking to promote their competitive product here ~to actively attempt to sell to another company's [hard won] fanbase, on that company's own website.

It's always seemed disrespectful, and very bad form IMO; and I usually ignore developers who do that [and their products].
I've read reviews that the gameplay is repetitive and relatively basic by comparison (to LoG); but not necessarily bad.
What a hell is this? I understand some inspiration but this is like seriously copy, paste. Some big companies would defintely sue for something like this, not sure if you fine with this guys.
IRRC, the game makes use of purchased assets. If somebody sold them something they didn't own, and was used in the game, the rightful owner would have an issue with them; but I don't think one can copyright a general method. Just the step based FPP is probably not an infringement. But then [IMO] some lawyers are crazy, and can be very aggressive over absurdities; like suing over the word "Scroll".