CloseDragon is an item that combines with the Build Driver, it becomes the Dragon Full Bottle as a result

another Build form- "NinNin Comic!"

Ninja + Comic = Naruto reference?

If that were the case then the form would more likely have an orange colour imo

Doesn't it say it includes the Dragon Full Bottle? You know, since Build can use it?

That's also possible. I didn't fully read the translation I saw

I wonder if Nitrouge will be a Rider in the future, since i'm getting Mashin Chaser vibes from him.

I think the Close Dragon item Kamen Rider Close has will allow him to use single Full Bottles so maybe that's why he's symmetrical.

You mean the BatRogue and BloodStark guys? They're getting their own transformation trinkets like Chaser and Graphite iirc

closer look at the BuildDriver & the Rider's weapon, DX DrillCrusher.