[quote]If you are like me, you may be struggling with the progression of The Perfect Fifth in the Polaris Lance catalyst. I was confused by it, thinking that getting kills with the exploding shot would work, but it is the burn damage from the explosion that actually counts. A good place to farm this is in the moon corrupted Expunge Mission: Styx. During this mission there are Harpies that spawn with a yellow HP bar. These are the ones you want! So what you do is get precision shots against the ads around the Harpies, and once you have the Perfect Fifth ready, fire a precision shot at the Harpies. The explosion leaves them with very little HP and the burn damage kills them. There are like 8 or 10 Harpies in total. I farmed this Expunge mission like 7 or 8 times last night and I was finally able to complete the catalyst, which honestly makes Polaris Lance even more awesome. I recommend it especially since scout rifles are getting a buff next season. Hopefully this helps! Good luck guardians.[/quote] Just completed today. Battle grounds or dreaming city with the taken are good areas to get a 5th. The key is to get four shots off on a yellow bar surrounded close prox by the reds. Or just keep going for head shots in a crowded area which the battlefields have; the nessus one with the tank like that strike is a good one. Polaris is a Great weapon with the catalyst and the new season splicer mod for fusion and firefly (energy accelerant is it?). Constant head popping and blowing everyone up. Took about three hours in the right places where enemies group together. Cabal are slow and you can get the precision by hitting them on the back in that orange/yellow area between shoulders which makes it easier. Worth doing.