I'm surprised by how long Yuri is lasting as actually effective in battle in spite of no new forms. The writing staff seems to really like him.
We actually have full scans now.
It seems like the name is spelled "Xross Saber" and it can change forms into "Featuring Saber", combining with Blades' and Ikazuchi's main books and "Crimson Saber", with the 3 bookset used for Saber's first upgrade back in the beginning of the series.
I hope it has more going on than those ridebook combination upgrades.
At this point it's totally just a base form Saber repaint but with a different sword horn on its headpiece.
At this point it's totally just a base form Saber repaint but with a different sword horn on its headpiece.