Well his sword splits into two pieces. Kento only sealed one half of the sword and we see that never uses the other half in either transformation or battle this episode. This is even confirmed on the official website

Nope. Kento managed to seal only one. Touma stepped in and stopped Kento from stealing both of them.

One of Ren's swords allows him to henshin, while the other concentrates his wind powers -- the latter was the one Kento managed to seal, which is why his fighting in this episode has a lot less of his usual style and powers (which is a nice touch!)

I'm late, once again, because I lost power while watching the episode, and I didn't get power again until I was ready to sleep.

I originally didn't have much to say about this episode, but seeing people point out something I wasn't thinking much about makes me really appreciate this one, so thanks everyone for pointing this out!

Anyway, looks like Reika will have some development going forward, which is great, and Ren might get some kind of new form or something, probably something like Lord Baron from Gaim, or Valkyrie's Jackal form from Zero-One, which I'm looking forward to. Kind of hope Ren comes back, and I like how Kento has a reason he's trying to shun Touma, though he'll eventually come around seeing how many times the future gets changed. I have a theory, but I'll save that for another time.

Next week: Falchion returns! (I'll watch the movie this weekend since it's short)

Why the heck would only sealing the non-transforming sword make any difference in how Kenzan fights? I mean, I can definitely see it's usage restricted in terms of gimmickry but it's still a piece of metal right?

It's basically just a regular sword now, I don't see why Ren has to be stuck with only using one sword now instead of his usual dual-wielding shtick.

I suppose it just a way to tell the audience that Kenzan is now handicapped in compairson to before. Tokusatsu is a very visual medium after all.