Also, pardon my low IQ, I think I understand how the head transforms now -_-++
All images from The Gundam Base Side One.
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EDITED: magazine scans of more details about Unicorn:
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Like what was said on SRW Hotnews: Do you ever suspect this is how MG Unicorn change his face?
Image from SRW Hotnews.
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Open the leg armor, and pull the thigh up to reveal the Psycho frame beneath. Does this means the leg must be detached first?
Image from SRW Hotnews.
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Part swapping? I don't see any need for that now. Terribly sorry for all the misleading information so far -_-
Image from Hong Kong Model League.
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Plenty of tricks with the armaments. Cool!!
Image from Hong Kong Model League.
Also, you can have a look at HCM-Pro Gundam Ez8 and Special Painted RX-79[G] on the same site.
On the other hand, Gunota Headlines reported that 1/100 Kyrios will come in January at the price of 2,730 Yen, along with HCM-Pro Ground Type GM (2,625 Yen).