You know how a lot of games have special attacks that ignore defence boosts or armour stats? Kuuga Ultimate has that as a passive ability, and his punches are so powerful they cause the person who got punched to burst open at the area punched and blood gushes out
Daguba is the in universe inspiration for Kuuga, and they have identical powers. Daguva can control the weather, summon lightning and can set things on fire by merely looking at them. Kuuga only showed that last one off, but as Ultimate is based off of Perfect Daguva, it's safe to assume he can do the same stuff.
As for weapons and other powers, this video shows enough
https://youtu.be/PPrZBSddsAw
Ultimate's versions of the weapons are the Rising versions. Ultimate has Pegasus' vastly increased senses, but Pegasus makes Kuuga suffer from sensory overload after 30 seconds, whereas Ultimate doesn't have this drawback. Kuuga also has a healing factor but it's rather limited, meaning he can shrug off most wounds after an hour or so
EDIT: forgot to mention Kuuga gets his weapons by transmutation, meaning he can grab a twig from a tree and now it's his gun. He can dualwield 2 Rising Titan swords and Rising Ultimate's canon, but often ignored as the original Kuuga never used it until a cameo