With fully marine equivalent stats (aside from typical Necron factors of Ini & Ld), an interesting weapon, an array of special rules and a good points cost for an elite unit. Despite fluff-wise being dishonorable assassins these will certainly see use in a lot of lists, which is a shame as I'm personally not too fond of the model (head is nice, rest is meh).
Their weapon can be described simply as a Rapid Fire Sniper weapon, which still sounds utterly bizarre, but single 24" shot or two 12" shots wounding on 4+ with rending cannot be frowned upon.
The special rules mostly revolve around their deployment, they can be kept in reserve to Deep Strike and if the enemy bring on reserves they can immediately Deep Strike down as if they passed their reserve roll (in the enemies turn!) and what makes this so good is one arriving enemy can cause any number of Deathmark units to appear.. Marines with Drop Pods will soon become annoyed I'm sure.
Their last ability is representative of their assassin nature, when they deploy they may select one non-vehicle enemy which their weapons wound on a 2+.
Former bodyguards of the leader of all the Necrons before they went into hibernation, Praetorians are now enforcers of honours within Necron society, travelling independently and making sure the Overlords aren't dishonorable in their actions so that the old Necron ways are preserved so that the old Necron way can one day return.
At first glance Praetorians are identical to Lychguard, their points are identical and apart from their attack values so are their stats. Praetorians only have one attack but are also fearless and are Jump Infantry which gives them a better chance of closing with the enemy compared to Lychguard.
Their Rod of covenant is treated as a power weapon in combat and can also be fired as a ranged weapon before they charge which is almost as good as their melee attack (6" range St5 Ap2). Alternatively they can exchange the Rod for a Voidblade & Particle caster, giving them a different ranged attack (12" Str6 Ap5) and an additional attack from two weapons, personally I'd prefer the Rod as Voidblades don't appeal.
They are a little expensive, but I expect to see them regularly as they are very nice models and an impressive unit. They can't select a Night Scythe, but you can't have everything.
The first and only Necron Walker (pictured above), these are an interesting unit and perhaps the only dedicated anti-tank choice in the codex, unless you change its weapon to something more anti-infantry.
With standard Necron AV values, Living Metal and Quantum Shielding they aren't bad defensively, despite being Open-Topped. They also have Move Through Cover, three attacks and are Str7 but lack any option of combat weapons which let them down, still they are able to kick Rhinos to death.
At 150pts their main weapon is a Heat Ray which each turn can be fired as either a Heavy Flamer or a two-shot Multimelta. For a few points more they can exchange this for a 24" Str7 Ap5 Large Blast cannon or for 15pts more a twin-linked Heavy Gauss Cannon which is 36" Str9 Ap2.
Their defining ability is their Targetting Relay which means if they hit a unit, all friendly models can count their weapons as twin-linked if targeting the unit they hit in that shooting phase.
The pictures are very intriguing and I cant wait to see the model but the stats themselves make me unsure of it, the Heat Ray is lovely and a couple of them are bound to ruin vehicles they shoot at (aided by the targeting relay) but they will surely suffer getting close.