Robox

Robox (1986) is a graphic adventure game developed by Laro Schatzer and Marc Pilloud for the Commodore 64 (C64). Adrian Demleitner researched it in depth for the research project CH-Ludens and conducted two interviews with the developers. The German-language game features numerous locations, a good parser, and challenging puzzles. It was released in 1986 by the German publisher Markt & Technik in "64'er Software Extra Nr.04: Abenteuer-Spiele - Volume 1", and is well documented.

Source: https://stage.chludens.ch/games/robox/