I played a rather pitched game with a good friend who is fielding the new Necron codex, and I have a few thoughts and observations I'd like to share with regards to Tau tactics while combating the deathless tide.
1. Scarabs aren't as effective effective against XV8's. I've noticed that the entropic strike special rule is HELL on vehicles, but not so much when it comes to XV8 combat teams with drones. Unless the scarab team is 10+ and the dice gods are with them, the XV's are going to end up stuck in combat, but not likely killed outright. I found this out tonight while having an XV unit tied down by those buggers; while they have 4 attacks per base (giving 50 on the charge) they are only weapon skill 2 and require to hit on a 4+ against suits of the garden variety, then the entropic roll of 4+, THEN the wound rolls of 5+... Which then the Tau player rolls for the remainder (which can either go really well or very badly) of x2, 4+ for the drones (assuming they're still there in combat), then the rest fall upon the XV's in ascending order to the team leader. So, in point, saying that once they roll to hit, then roll for entropic strikes, THEN roll 5+ to hit, they probably aren't going to do much damage, and will probably take a couple of turns to whittle you down where you feel the pain. You're gonna be stuck, but that's going to be a hard kill point to score (at least harder than a vehicle)
2. Anrakyr the Traveller is friggen awesome if you put him in a command barge and hang around vehix as much as possible. He's cheaper than most other overlords (minus Destroyer Lords, but I'll get to that). he has a special rule which allows him to take control of an enemy vehicle and fire all of its available weapons and control it like it were a Necron unit. The vehicle can't move, but it can swivel its turret or sponsons and fire all of them at a friendly unit. Not to mention he gives one selected unit Immortal status in addition to giving the declared unit furious charge and counter attack. He comes stock with a warscythe, has 3 wounds, and can play hell with a mechanized opponent.
3. Destroyer Lords. OMFG... These things are Toughness 6, 3 wounds, 3+ armor (2 if you give him the upgrade), is jump infantry, and can be attached to whomever you want. Effing amazing and hard to kill. Did I mention he's cheap too?
4. I've noticed that the new codex makes Tau a little less easy to steam roll when facing a Necron army. Warriors are a 4+Sv now, and most tau weapons with any punch are AP4 (making missile pods FAR more effective), Reanimation protocols are at a 5+ (meaning you may actually KILL some of them before they get to you), The Storm Lord's night fight ability is rendered moot by a simple black sun filter or marker light, vehix with sensor spines can ignore difficult and dangerous terrain, multi-trackers allow you to move a vehicle 12" and still fire (making anything looking to assault your hammerhead need a 6+ to hit you), Disruption pods render all shooting attacks moot on a 4+ even against eldrich lances and tachyon arrows.
5. Monoliths are now 'deepstrike or nothing' vehicles. I've seen my buddy now field his monoliths 3 times and lose them all by turn 3, instead of dropping them close in by an unsuspecting enemy and pulling a unit of immortals or scarabs through to negate any plans a shooty army would've had against the far game. It doubles the mobility of your T800's not to mention brings some pretty nasty firepower to the board if you can get it close enough.
I'm not saying Tau now have the upper hand, but rather I think that Necrons now have to work much harder for their lunch money if they are looking to eviscerate our fishy friends with the schnazzy wargear.
Thoughts?