Remember that this is Kouta we're talking about. He will not escalate beyond a certain point unless he's absolutely sure that there's no other way to get his point across. Even though he has the power of a god, he'll still hold back as much as he can to give the other person a chance to survive.

The only reason he didn't hold back against Kogane is because he was a monster, that there was no reasoning with him. A psychopathic, destructive artificial "god" that would threaten everyone and everything if not destroyed. Note that one of the very few times you can actually hear Kouta speaking with real hatred in his voice, his words dripping venom, is when he addressed Kogane.

That does make a lot of sense. Explains why he didn't just Kiwami Lord Baron into the ground when he was using banana arms.

That and Kaito and Kouta were pretty evenly matched in general.

It's possible that the movie's villain is able to restrict him in some way. Like maybe he has to use all of the golden fruit's power to keep his new planet from completely dying, so he's limited to what his belt can do while he's fighting.

My guess is that Kouta brought along a few toys.

That or they find Ryoma's stash.

My guess is Kouta is able to restore their Sengoku Drivers. That, or the movie takes place BEFORE the end of Gaim.

That was my thought to. He already remade the Kachidoki Lockseed after Redeyu destroyed it in their final battle. I doubt he'd have much trouble rebuilding regular Locks.

I believe it's already been confirmed that one of the villains in Gaim, that is currently living on the new world Kouta made wants to spread the Helheim curse back.

Considering we see both Shin Zangetsu and Normal Zangetsu in the set picks, my guess is that hell get the last genesis Driver destroyed by Ryoma and have to get a sengoku driver.