Siege of Aotis

The Siege of Aotis was an Imperial defensive campaign undertaken by several companies from the Storm Sentinels Space Marine Chapter in the defence of the notable Hive City of Aotis against a newly arisen, and formerly unknown, Necron Dynasty. Though the Storm Sentinels eventually emerged victorious, they suffered grievous losses during this bloody and grinding conflict.

History
As the ninth century of M41 dawned, on an unnamed world, a notable Hive City named Aotis was besieged by a newly arisen Necron force. The Hive City's Planetary Defence Forces were unable to hold back the Necron force due to the massive numbers they faced. The Storm Sentinels 4th Company (accompanied by auxiliary squads from the 1st and 6th Companies) was sent to repel the Necrons from destroying the city. The Space Marines were unable to hold back the Necrons as their entire auxiliary squads were destroyed and the 4th Company was nearly destroyed if not for a Squad of Veterans holding back the Necron tide.