You'll need 500 Precision kills and 500 SIVA Particulates in order to complete the Catalyst. Once you’ve earned Outbreak Perfected, you’ll be able to gather SIVA Particulates and get the Outbreak Perfected Catalyst, a perk which increases nanite damage. The Outbreak Prime Exotic pulse rifle was added to Destiny 2 last week as the revitalised Outbreak Perfected and it comes with quite the challenging questline.