"Is there any super bad-ass Catholic weapon around out there?"
You mean besides the Spear of Longinus, which could cause empires to rise and fall?
There’s Ascalon, the lance (or in some versions, sword) that Saint George used to kill that dragon you might have heard about.
There was Joyeuse, the sword of Holy Roman Emperor Charlemagne, which was said to contain bits of the Spear of Longinus in its pommel.
Charlemagne’s paladin Roland had a sword called Durendal, which had in its hilt one of St Peter’s teeth