Complete the indicated task to unlock the achievement.

Achievement	How to unlock
Adamantium	Find the Lightning Claw.
Anything Formed	Find the Plasma Gun.
Apothecary Ordyss	Find Brother Ordyss.
Brother Barathon	Find Brother Barathon.
Brother Kael	Find Brother Kael.
Brothers In Arms	Find all of Squad Scipio.
Come Get Some	Find the Chainsword.
Epistolary Radamus	Find Librarian Radamus.
Fist of Dorn	Find the Thunder Hammer.
Get to tha' Stompa!	Get inside an Ork Stompa.
Gordon's Alive	Find the Blessed Blade.
Herald of Death	Destroy the Herald of Oblivion.
Herald of Life	Destroy the Herald of Oblivion and live.
Herald of Shame	Escape the Herald of Oblivion.
Hidden Archeotech	Find a Signum.
Sabotage Reactors	Sabotage the plasma reactors.
Sabotage Warps	Sabotage the ancient warp-field generators.
Saxon Harold	Find the Master-crafted Storm Bolter.
Sergeant Valerius	Find Sergeant Valerius.
Sword of Ancients	Find the Relic Blade.
Sword of Omens	Find the Power Sword.
Toasty Falsetto	Find the Heavy Flamer.
Unlikely Ally	My enemy is my friend!.
Zathael's Fury	Trick a dreadnought to its doom.