Touch of Malice is an Exotic scout rifle you will get from Eris once you complete her quest chain in Destiny: The Taken King. It’s not so simple to gain it, as you will have to collect more than 40 Calcified Fragments and kill raid bosses. Let’s take a look at how to get it, anyway, in five steps.
Collect 5 Calcified Fragments for Eris and begin the quest Shattered Past. With 15 Calcified Fragments you will then unlock Eris’ second quest called Hunger Pangs and will have to kill Taken Centurion Bracus in the Salt Mines in Bunker WAR-4.
Complete The Old Hunger, a quest you will trigger accessing The Fallen King raid. It requires you to kill 3 bosses from new Destiny raid and collect 3 different items: Blade of Famine item from the Warpriest, Shroud of Ir Anûk from the Deathsingers, The Ravenous Heart from Oryx.
After collecting these items, Eris will have another quest for you asking to collect 25 Wormspore, 50 Hadium Flakes and 50 Weapon Parts. Eris will reward you with Antiquated Rune for those materials.
Collect 30 Calcified Fragments and the quest chain will start again. Talk with Eris and go to kill Morgath, Lore Keeper, who’s located in the Black Garden at the very end of The Undying Mind Strike. Return to Eris and get a Stolen Rune after collecting 45 Calcified Fragments.
Get back to the base on Phobos, kill the Wizard and claim the Essence of the Feast. You’ll have to complete the Fear’s Embrace mission on Phobos and defeat Mar-Zik, the Blightcaller, who spawns at the very end of the fight with Echo of Oryx (approximately at 25% of his health).
Congratulations, you can now get the precious Touch of Malice from Eris!