Of course I do, Rogue Traders aren't in the business of admitting things like that too often! Plus, it reminds me that there is no such thing as too many layers in a plan, especially when dealing with good players...
But back to the business at hands, another important is experience fighting wars, especially on a massive scale; the Imperium and Chaos may have been at war for 10 000 years, humanity may have been conquering the galaxy for twice that time, and the Tyrannids may have a hive minds capable of waging wars simultaneously throughout most of the galaxy, but no one alive has experience fighting a total war on a scale quite like that of the War in the Heavens. The Eldars barely remember it as a legend, and a few ancestor spirits deep within the Webway may still hail from those dark days millions of years ago, but every single necron is a veteran of this conflict, and although most may have forgotten nearly all of it, some still recall them, and these generals are the survivors of millions of years of conflict against everything the galaxy could throw at them, from the wrath of the Old Ones themselves and their myriad pawns to the bling fury of the betrayed C'tan. This makes the Necrons by far the supreme strategist in the galaxy, with only their own pride and time honored traditions stopping them from truly unleashing this advantage. Of course, some factions can counter this; the Eldars have a much greater understanding of divinition, allowing them to more or less cheat, and the Orks are entirely unpredictable to logic, making them relatively hard to counter reliably despite millions of years fighting their progenitors.
Moreover, it is important to consider is the "wildcard" technological factor. Necrons are the undeniable masters of technology in the setting, and, unlike most other species, have a rather open mind when it comes to exploring different branches of science. With thousands of competing Cryptek conclaves, each revolving around one of dozens if not hundreds of esoteric disciplines unimaginable by the rest of the galaxy, the Necrons not only have an advantage in potency, but also in technological variety. As such, although this is not really well covered by the crunch, it is impossible to reliably predict what technological marvels or horrors a necron force may carry, and what new or previously unknown devices they might choose to unveil. Therefore, with the exeption of the Eldar (who probably have records of most of the necron's capabilities lying around in some dusty corner of the Black Library) and the Tyrannids (who can evolve fast enough to reliably counter newly appeared technologies in future encounters), most factions involved in the conflict simply cannot reliably predict their likelihood of success in any single encounter with members of the upper Necron hierarchy, which seriously undermines any attempts at waging a serious war effort against them.
Finally is the questions of weapons of mass destruction; most species in the 40k universe can ravage planets, and possibly destroy a few using convoluted methods (asteroids, gravitational tears, warp portals, etc.), some, like the Imperium and the Eldar, even get planet cracking firepower relatively easily, but usually in limited quantities and flavors, but the Necrons remain the best at both scouring the life from a planet and utterly annihilating them. The War in the Heavens involved titanic clashes in which the very stars were extinguished and used as weaponry, astrological phenomenon including black holes where mastered and used as tools of war, and the very universe was torn asunder when the Immaterium was torn from the Materium. Although they might lack the power (in raw energy or soul powered C'tans) this weaponry, or at least to knowledge to create it, because the Necrons who fought in the War of the Heavens are the same ones as today, still lies within the depths of the Necron tombs, and, here again, only the bickering and pride of a decaying culture is stopping them from making full use of them.
tl:dr Necrons have the best strategists in the galaxy, have the best technology (and no one else really understands it, which makes countering it a *****) and the best super weapons if they can find them, and that's a big problem for everybody else in the galaxy if they could just wake up from their nap and stop bickering like 5 year old children with a holier than thou complex.
Edited by MorioMortis, 22 July 2014 - 06:10 PM.