Ok, these are still 2nd Quarter Toy Listing 'rumours'. Kamen Rider Saber's Final Form is said to appear in June. Isn't it a bit too early?
Toei already knows that we'll troll them if they make one more form like Kamen Rider Decade Complete Form & Kamen Rider Grand Zi-O, so this time they seem to have use a different trick on the same strategy.
With the form reveal of Kamen Rider Saber Primitive Dragon having a Large Ridebook on the chest, they were multiple people who were assuming that the form suit will contain multiple Ridebook. But we were wrong. Instead of Ridebooks, they are going to attach Seikens on the suit. It has three different forms. Yes, the Final Form has Form Change.