The kit's instructions call it the "High-Speed ​​Mobile Zaku." I remembered it by the name in the post title, but I wonder if that's because of the influence of the game "Gihren's Ambition"? In the manga Thunderbolt, it was active as the "Octopus Zaku." I remember being shocked when I saw an illustration of this mobile suit in an MSV-related booklet I got at a model shop when I was a kid, thinking, "Is this really a Zaku?!" Apparently, the mobile suit is a modified version of the second Zaku used for Psycho-Comm testing, and its original model number was MS-06Z-2. And then it transitioned to the model number MSN-01 as the base for the development of the Zeong.

048 MSN-01 Psycho-Comm High Mobility Test Zaku | ヒロユキマル's Gunpla works