This is a story mission where you can obtain the year 3 Gjallarhorn. It begins with a large horde of Fallen from the House of Devils but are not Splicers. Once you clear them out you will find this small room with a table. On the table there will be Gjallarhorn parts scattered across the table. You will have to scan it with your Ghost. You will have protect your Ghost from countless Dregs and Vandals (Again, not Splicers while your Ghost scans and rebuilds the Gjallarhorn parts. Once you have completed this task, you will be gifted with the almighty Gjallarhorn and you will be able to equip it and kill everything in sight. You will witness its' true destructive properties and waves and wavs of Splicers only attempt to stand up to your glory.