Outbreak Perfected is a Pulse Rifle that is acquired from completing the mission Zero Hour.
There are several options for you to choose between depending on your progress.
1. Unlock the Questline
To get access to the Zero Hour mission you first need to have completed the Planetary missions on Titan for the Rat King and then find a secret Fallen Transponder in the Heroic Adventure – Bad Neighbours. Once this has been completed you need to visit Lost Sectors and collect the 6 hidden Nodes to charge up the Fallen Transponder. Once this is done you will gain access to the Zero Hour mission in the Farm.
2. Zero Hour Mission “Normal”
Once you've unlocked the questline, you now have to complete the Zero Hour Mission. You will receive Outbreak Perfected upon completion of this mission.
3. Unlocking the Catalyst / Zero Hour Mission “Heroic”
If you wish to upgrade your Outbreak Perfected you must complete the Zero Hour Mission on Heroic difficulty. Once you complete the mission you will receive the catalyst and 20% progression on the SIVA Particulate step of the catalyst. You can only receive 36% progression on the Catalyst each reset, so to complete the full Catalyst progression you will need to do one Heroic Zero Hour completion every week for a total of 3 weeks.
4. Time trial for the Emblem 'Quarantine Zone'
By completing the Normal version of Zero Hour within 15 minutes you will unlock the Triumph “Expedited Exfiltration” and be reward with the cool Emblem.