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Belgian Malinois Sounds, Blackreach can be found by traveling through Alftand, Mzinchalef… The controls consist of a Lexicon Receptacle and four positioning buttons embedded in pedestals. Auf den Turm von Mzark stoßt ihr im Thread „Die letzten Überlebenden“. I've started the 'Discerning the Transmundane' quest, went to the Tower of Mzark in Blackreach, then tried placing the lexicon on the receptacle.