Latest Tamashii blog has some very interesting teasers

http://tamashiinations.blog.jp/archives/9343404.html

" From the "Kamen Rider Saber" series, which is being commercialized one after another, the Northern-based swordsmen have finally gathered! ?? "

" That Kamen Rider suitable for the 50th anniversary year of Kamen Rider's birth will reappear in SHFiguarts with new coloring "

" From the SHFiguarts (true bone carving method) series, it will be the first appearance at this event! A new character will be exhibited "

" The Kamen Rider, whose planner is worried about how to make it three-dimensional as SHFiguarts, will be exhibited as a reference exhibit "

Also pay close attention the the font color used. Tease for SS Black RX and dare I say, Decade Complete 21 ?

The northern-based Swordsmen have finally gathered?1

Would most likely mean... All of them?! Slash, Buster, Kenzan, Espada, Blades, Saber (and Yuri lol). That's pretty surprising for them to just dump them all in at once, but considering Saber has been pretty hush hush in releases, I guess it's not too surprising.

Kamen Rider most suitable for the 50th anniversary. Green font. My gues is Rider 1's original colors. Hopefully.

New Seihou, a new character will be exhibited. This one is pretty vague since it doesn't completely imply it's a Kamen Rider. But the font being in silver and green makes me think it's V3. Could be an Ultraman, though, but I don't recall any green/silver Ultramen.

The Kamen Rider whose planner was worried how to make it 3-dimensional
This one's funny since I'm betting it is indeed SS Complete 21. Who else could it be that would make a planner/sculptor worry? If nothing else, the similar colors could also yield Putotyra.

I swear to god if they make it so that all of the Northern Base Kamen Rider SHFs are being released at once, I'm going to flip out in excitement/frustration because I have zero doubt that they'll be P-Bandai. Will prioritize getting Slash, Buster, and Saikou.

Hopefully this will include Saikou Shadow with X-Swordman Powerful and Wonderful parts too, in addition to Saikou X-Swordman Colorful.

I don't believe they'd release all of them at the same time. My best guesses is one of them taking up at least one slot per month along with other products.

Regarding Saikou, I think X-Swordman would be released solo, while Shadow would be packed in with the parts for Wonderful and Powerful. My only wishes is that X-swordman comes with an alternate WRB that shows his chapter 1 form, the le funny swordman form. Would be nice to have Dragonic hold him.

If Shadow really will be sold separately with the Wonder and Powerful parts then knowing Bandai it'd make sense for the chapter 1 form to be included with that instead of X-Swordsman. They'd probably release it all under a "Saikou Shadow w/ accessory pack" title or something.

https://i.imgur.com/gzm0Ug6.jpeg
I know. Just would be the nice to have that kind of display option early and without having grab another Saikou for it. They were kinda extra with Thouser by giving him a Raidriser, so I have the 'lil bit of a need for to them to be extra again.

I'd wager that we never see Shadow with X-Swordman prototype already being shown off.

Very interesting! For Rider 1 I've already decided to go with the original SHF but it's nice to see this happen

Wouldn't necessarily say that, since Build NinninComic is getting made, long after they stopped making SHFs for the "non-main" forms. Even if we take into consideration that Sento's/Takumi's dad is who it's supposed to represent.

Build sold incredibly well, though. Could rely on Saber doing similar numbers and how easy they can re-use parts from the X-Swordsman that's gotta be coming.