Solgaleo?

[Dragonstrike]

The track is Electric Mudkip's (now Emdasche)fanmade Solgaleo theme from back when Sun and Moon were first revealed. It was the theme for the Championship trainers before the themes he made specifically for the finale were implemented.

Here's the other ones he did that weren't originally made for Uranium:
VS Urayne is his Magearna fan theme.
VS Actan and Lanthan is his fan theme for Yveltal.

And the ones he made specifically for Uranium:
Wild Pokemon
Nuclear Wild Pokemon
Gym Leader (and Leader's last pokemon)
Trainer battle.
Theo (both battle themes)
Championship Trainers (not Solgaleo, the new one)
Snowbank Town
Victory Road.
Nuclear Plant Zeta

Those are all the ones I remember off the top of my head. He has all his tracks from Uranium in a playlist on his youtube channel, by the way.