The haunted swamps of Vanquellis IX

 Necrons awaken in the Vanquellis system!

 M40.171.022 - Imperial Fists discover forgotten tomb below desolated death world

 "Again, Nothing, Lord" the crewman stated when Chaplain Caran Furn ordered him to perform another sweep with the long distance auspex systems. "We still have no hint as to where the colonists went, Darellus." the warden stated matter-of-factly to the vessels commander, Captain Harken. His stern face gave no visual hint away to show his opinion, but the warrior-priest knew his battle companion long enough to know his thought process. They have been waiting for hours now in this high orbit position over the swamp world of Vanquellis IX, with the old Astartes making up his mind. The imperial archives were lacking any sort of communication from the planet for years, and the tithe-keepers were growing suspicious, and the subsystem magistra administratum had managed to sway the Astartes to sweep the system on their way en-route.
Just when his lips started to shape an order, the Chaplain knew the time was ripe and read his mind.
"Signal to teleport chambers. Ready Squad Varachez. I will meet you there immediately".
"What do you think you're doing?" the Brother-Captain burst out, half in jest.
"Getting a closer look, as you were planning to order, I assume."
"Not entirely, old friend. I'm joining you on this", the old Imperial Fist smirked, and the ship-wide vox caster transfered his next sentence "All crew on battle stations. Ready Squad Jettar, Hant, Shalem and Venerable Pakkanen. We are making planetfall in eighteen minutes."

Chaplain Furn and Squad Varachez teleports into the swamps

The strike force facing a C'tan Shard

Venerable Pakkanen spraying the Necron with a hail of bullets

Astartes claiming a fortified position

Squad Shalem taking aim on marching Necron warriors

Pakkanen and the C'tan clashing into each other in the centre of the battlefield