This kit is the SD Musha Gundam Shin from the SD Gundam Sengoku Heroes series, released in 1996. A bit of background on the Sengoku Heroes series — it's based on characters from a manga called "Puramo Wars" (Plamo Wars), which ran in Comic BonBon from 1994 to 1998. Like Plamo Kyoshiro and Build Fighters, it's a series centered around customized plastic models, and a total of two kits were released.
The overall package has a similar feel to the Chibi Senshi line — it's a simple, budget-friendly kit that comes in a side-opening box to match. The biggest highlight is that you can easily swap the equipment around to represent the three Musha brothers (Shin, Kou, and Dan), with eye seals in yellow (Musha Gundam Shin), green (Musha Gundam Kou), and red (Musha Gundam Dan) respectively. You can also deploy the weapons on the head and reposition the feet and wings to recreate the Kattobī Jet form.
The basic articulation is about as low as it gets even among SD Gundam kits — the neck, feet, and shoulders do rotate, but there are so many parts in the way that the range of motion is extremely limited. The real appeal here is probably the fact that you can recreate three different forms and transform it into a flight mode with just a small number of parts. One other notable feature: there's a connection pin stored under the hip joint that you can remove and plug into the front or back of the body, allowing you to chain multiple kits together in a row.
Anyway, this is a pretty obscure SD Gundam, so it's more of a "oh, something like this existed!" kind of find. That said, for a 300-yen kit, it's actually a surprisingly well-packed little set. :-)
AIThis page was translated by Claude Sonnet.