Rising Ultimate Kuuga was in a hard battle against someone who was BETTER than him, so why didn't that break his belt and/or kill him? And yes, yes it was the transformation. The sheer power being generated, the belt just could not take it anymore.
Daguba had something similar to the stone in Kuuga's belt, and it didn't spontaneously destroy itself. Why should Kuuga's? It was due to the battle.
Besides, Decade's and Kuuga's battle against ShadowMoon didn't even last enough for them to get any hits on him. We know Tsukikage was more
skilled than Tsukasa and Yuusuke, but that says nothing for his power. Look at the battle again. He used his sword to out range Kuuga's punch and used energy attacks on him while thrusting his sword into Decade. He wasn't even hit by neither of them nor directly overpowered them at any time. Tsukasa and Yuusuke just weren't good enough to actually get past his sword moves.
(supposedly impossible to damage--someone who's seen RX can let me know if someone ever conquered that)
Shadow Moon randomly hit him out of it during one of his returns. In any case, I thought that might have worked due to the stun effect that Faiz's Rider Kick uses. And really, the tournament matches were completely rigged.
RX was standing right after that, but he "lost". Decade fell several times during his 3 matches, and yet was never eliminated.
Also, someone said something about giving new forms to all the Riders. ...Really? I mean, really? We didn't see them use the power-ups they had.
That's why I also said that it wouldn't work with the way most weren't even featured much after their own arcs ended... but, really, I'd like to see it. It'd give more identity to Decade's AR Riders.
Rising Ultimate Kuuga is automatically associated with Decade, not the original Kuuga series. I'd have liked to see more things like that for the others AR Riders too, although, obviously, if they were going to do it, they'd need more screen time.