This is an HG version of Staymen, the man behind Dendrobium, who is rather obscure on his own. It's a fairly simple kit when assembled, but after some smoothing out the seams and some minor painting, it looks quite sleek! The folding arms are also faithfully reproduced.
The specs are set in a good way (lol), and it doesn't stand out much among the 0083 MS, but it seems to have excellent performance. Some say it surpasses the MS from the Gryps War? (Well, it does seem stronger than the GM II.)

RX-78GP03S Gundam Prototype Unit 3 (Stamen) | 121kry's Gunpla works