|Battle Cry||"Primus inter pares(First Amongst Equals)"|
|Founding||Unknown, possibly Second Founding|
|Successors of||Ultramarines (or possible loyalist Iron Warriors decendants)|
|Allegiance||Imperium of Man|
|Colours||Gunmetal and black, with silver helms and aquilas|
The Silver Skulls are a Space Marine chapter created in an unknown later Founding. They've been around since the days of Rogue Trader, decapitating heretics, covering their heads in silver and keeping them as trophies. This practice is also employed by the White Scars on the skulls of those captured by the Hunt.
Mostly known these days for starring in short stories and a full novel by Sarah Cawkwell.
Some people think that the Silver Skulls, like the Blood Ravens, are possibly a loyalist fragment of a Traitor legion. In particular, people have considered the possibility that they are descended from the the Iron Warriors, the Ultramarine part being a cover Guilliman gave them. The evidence for this is mostly circumstantial and derived from narrative convention, but it's a very strong narrative convention to some. First of all, the fluff had always explicitly stated that they only claimed to be Ultramarine successors (ever since their introduction in 2nd Edition, interestingly enough). Their livery consists of a silver skull that looks extremely similar to the permanent iron mask of the loyalist Iron Warrior warsmith Barabas Dantioch. In the Imperium Secundus during the Horus Heresy, Dantioch and his Iron Warriors were accepted and beloved by the Ultramarines as loyalists, and eventually proclaimed that they marched for Maccrage. Of course, this is all just narrative convention and thus is unconfirmed for now. As an aside, the Silver Skulls' penchant for prognostication is explicitly stated to come from their chapter home world's culture, and thus shouldn't be seen as evidence for who their Primarch is.
Note that the most recent Space Marines 8th ed (2017) states outright that the Silver Skulls are directly descended from the Ultramarines, being one of the "Scions of Guilliman". However, you might still think this leaves the possibility that the Silver Skulls were snuck in as a successor during the Second Founding, being loyalists from a traitor legion. Against this, Aaron Dembski-Bowden explicitly stated on the Bolter and Chainsword forum that the Blood Ravens are not a loyalist splinter of a traitor legion (or rather, that they're not allowed to have a definitive answer to their origins), and that chapters with murky origins are just bad writing to make them stand out, confusing readers about their basically vanilla origins. He says he has had the lowdown straight from the IP people of GW.
Then again, their new Chapter Tactic favors retreating to fight again another day. Exactly what Dantioch wished to do against the Hrud. Which caused Perturabo to exile the Warsmith from the Iron Warriors in the first place! WHICH LED HIM TO HELPING TO FORTIFY ULTRAMAR! Although considering their somewhat Khornate hobbies points to them being a bit bitter about the whole affair.
That said, ADB also said that the fluff intentionally associates some chapters from two or three foundings with "Traitor/dubious gene-seed", but without confirming or denying if the fluff is true. The question is whether you believe the Second Founding to be one of the foundings ADB had in mind. If so, it is justifiable to read the Silver Skulls as a loyalist fragment of a traitor legion. If not, the Silver Skulls are just Ultramarines successors. There has never been as much traction to the Silver Skulls' murky origins in fandom as was the case for the Blood Ravens, and so you should not expect GW people to come out and explicitly clarify any intended/unintentional ambiguity.
The Prognosticator is the Silver Skulls equivalent of a Librarian. Prognosticators use various forms of divination to predict the future. These forms of divination often use psychic Tarot Card wafers, Rune Stones, etc. It is with their predictions that the Silver Skulls choose to go to battle, because their homeworld's culture places great reverence on psykers. In addition, they also serve as part-time Chaplains, for aforementioned reasons. Although if you think about it, that's a genuinely terrible idea, even by the standards of 40k's 'Put a lunatic in charge and assume it'll work out ok' style of poor choice making. Putting the dude who is most likely to get possessed by a daemon in charge of the spiritual well being of everyone else ? That gentlemen is exactly the kind of thinking that leads to minor problems.
Recent Activities(Getting rekt by the Crons)
The Silver Skulls have been getting kicked in the balls by some other silver fuckers recently, with a Necron Tombworld awakening beneath one of their fortresses. The necron lords made a game of it, with everyone taking turns to see who could kill the most defenders. Two weeks later one lord won and the Silver Skulls 4th company was annihilated. The rest of the chapter attacked the crons, blockading the dead system of Lazar without any explanation. Making sure not to tell anyone about the extremely dangerous foe who was likely within striking distance of Imperial worlds. Anyway the Skulls destroyed the primary tomb world, which of course caused all the secondary ones nearby to activate, turning it into a full scale war.
As if this whole thing wasn't bad enough for the Skulls, Anrakyr showed up to help the Necrons, and in the final battle used his powers to turn the guns of the crashed battle barge the Skulls were fighting around against them, then killed their chapter master. At that point the Skulls said "man, fuck this" and left, making sure not to let anyone know they lost the war, or that there was one to begin with. Because the moral of the story is to never tell anyone about the massive threat that just handed your ass to you if it means you'll look bad.
- Or because the last thing the Silver Skulls need is to incite mass panic within the ranks of Imperial citizenry, because the Inquisition says that's bad. 'Mkay children?
- No, it doesn't. The Inquisition says it's bad to spread dangerous knowledge, so they'd definitely support keeping the citizenry ignorant of imminent threats, but mass panic isn't nearly grimdark enough a reason for them.