[806mtson]

Imagine if the Fullbottles of Kamen Rider Build because what they are based upon and the Special Full Bottles had special Combinations with other objects. These are my ideas.
For each Best Match, you can get both Fullbottles at once. For each of them, they have 3 Modes, Fullbottle Mode, Basis Mode, and Halfbody Mode. Fullbottle mode is kinda obvious. It becomes the Fullbottle in question. Halfbody Mode is when it can combine with the other Fullbottle to create that combo. For Basis Mode, it can become what the Fullbottle is based upon. The Rabbit Fullbottle becomes a Rabbit. The Tank Fullbottle becomes a Tank. The Gorilla Fullbottle becomes a Gorilla. etc. When you use the Dragon Fullbottle, you can combine it with a Transforming Cross-Z Dragon to become Cross-Z. Each special Fullbottle becomes the thing that is called out when you put it into the Build Driver (Like Dragon Magma, North Blizzard, Killbus Spider, and Grease). The Rider System Evolbottle becomes a base humanoid which works with the other Evolbottles becoming Armor, instead of becoming a Halfbody. The Legend Rider Fullbottles which work with a pre-established Fullbottle like Momotaros (works with Densya), Rider Card (works with Camera), Medal (works with Taka), Yujou (works with Rocket), Mahoutsukai (works with Diamond), Orange (works with Lock), and Parka (works with Obake) all have added faceplates which you can substitute the main Halfbody faceplates with faceplates which look like the Kamen Rider they were based upon (Den-O for Momotaros, Fourze for Yujou, Wizard for Mahoutsukai, etc) to make them look like they have the Kamen Rider's head. There will be alone purchase versions of Densya, Camera, Taka, Rocket, Diamond, Lock, and Ghost to allow for people to keep the KaizukoRessya, BeetleCamera, HawkGatling, PandaRocket, GorillaMond, KeyDragon, or MagGhost Best Matches together if they want both. For those who want it more accurate, there will extra releases of the Legend Rider Best Matches in more accurate color schemes. The Metal TankTank Fullbottles will be released together. Overall, it is meant to be something to be collected. The Fullbottles themselves are all the same size as the standard Fullbottles and even come with rails as accessories which can be used for you to use them in the Drivers. Lost Bottles just transform into the things they are based upon. If they don't have a "Best Match" in their regular forms (therefore Excluding Bat), they don't have a Halfbody mode.

In this new release, they could release the missing Fullbottles and Evolbottles (Crocodile, Remocon (CrocodiCon), Kyoryuu, F1 (F1saurus), Keisatsukan (working with F1 to make the Drive Best Match), Kappumen, Energy Drink (CupEnergy), Showa Rider, Heisei Rider (special Combo), Tank Evolbottle, Lock Evolbottle, and Dinosaur Evolbottle) to complete the Best Matches/Evolutions you can make. And they could re-release an Updated Build Driver with the remaining Heisei Rider Best Matches (Kuuga, Agito, Ryuki, Faiz, Blade, Hibiki, Kabuto, Kiva, and Zi-O). Seriously, Kabuto could use the Kabutomushi Fullbottle as part of it's Best Match, Faiz could use the Smapho Fullbottle as part of it's Best Match, Hibiki with Mic, Kiva with Bat, Ryuki with Dragon, Zi-O could use the Heisei Rider Fullbottle with the Watch Fullbottle, and Ryuki and Blade could share a new "Card" Fullbottle (not the Rider Card Fullbottle of the Decade Best Match, just a normal Card).

Now, on to what the more, err, weird Fullbottles could become. Yujou could become hands that could work with 5 mm ports or 2 smaller humanoids. Gatling could become a 5 mm port compatible Gatling Gun (5 mm ports are used for Transformers). Overall, it is all about Transforming.