I did a couple test games vs necrons and I found mindshackle scarabs to be very annoying :P Basically, during an assault one enemy in b2b with a guy with these scarabs need to pass a 3d6 ld test or they smack themselves (or their unit) during the fight. Thankfully, the unit doesn't actually attack itself, it simply inflicts a d3 hits, but it means you hit your own unit at least once if you don't pass that test.

A ld 10 test on 3d6 will fail about 50% of the time. So this means that really uber assault models like greater demons, skulltaker, or even a bloodcrusher model are negated half the time by being in b2b with a necron lord or cryptek. I found this out by having an unwounded demon prince of nurgle (wings, noxious touch, gaze) and a 5 man unit of plaguebearers killed by a big unit of crons that had 3 guys with scarabs in it.

My thoughts on counter tactics would be that demons players need to find out which models have these scarabs and avoid them and their pile-in move as best as possible. This may involve tossing a chump model into b2b with the target in question or using wings to ensure you charge from a distant flank from the scarab holder.

Any thoughts?

I haven't used Mindshackle Scarabs in my own army, and haven't heard of anyone else facing them yet. I think most Necron players just prefer to spend the points on more guns. Against an army with lots of powerful combat units like Daemons though I can see why they would be useful.

Avoiding the character completely isn't going to be easy, since you have to move at least one model into base contact with him if you can. I think your idea of moving a model that is only average in combat into him as you suggested is probably your best bet, and then try to take out any unit he is with so he has to take a morale check with a heavy modifier.

The alternative is to try and take him out with shooting first (Flamers and Mawcannons are good for this) or engage him with a Soul Grinder (they have no Ld value so can't be affected by the scarabs).

I agree with most things said by JonathanC, however soul grinder counts as vehicles/walkers so they have LD10.

Try using BLs to kill his lord, If you use IC or expensive units then you are giving him/her your own units to to harm you.

I didn't realise that Walkers count as Ld10, and couldn't find it in the main rulebook or FAQ. I know that they sometimes do against certain effects, or if they are psykers like Grey Knight vehicle, but its not listed in the Mindshackle Scarabs rules themselves which would normally clarify that kind of special exception.

Not saying you are wrong as such, just not sure where the Ld10 rule is.

Have to agree though that sending in a decent sized unit of bloodletters is probably the best way to get him.

hmmm I'm thinking of the GK hammer that banished to my slaughter, so I thought that vehicles are leadership 10, as said so way before. . But I think you are right certain effects must be involved. i.e blood angel dreadnought psyche powers, there fore as LD 10
However if's it's not stated in the rules that it can not effects vehicles then I'm going to use a DC dreadnought with blood talons. or a SG

Alternatively just put a lot of models in base contact with the model that has mindshackle scarabs. The model that gets to attack his unit is determined randomly from those in B2B.

Also note that during assaults independent characters are treated as separate units so if they fail the test they hit themselves in the face.

Things to watch for from the new Necron codex are Scarabs, Mindshackle Scarabs, and Wraiths.

Mindshackle scarabs can be annoying but they're only on Overlords, Lords, Destroyer Lords and a couple named characters. When normal lords are attached to a unit they act like sergeants since they don't have the Independent Character rule. Swarming the Lord with generic guys or only basing it with one generic guy significantly decreases the effectiveness of Mindshackle scarabs. EXPECT this wargear on every Lord.

Canoptik Scarabs are the Must Take unit in Codex: Necrons. They easily eat through vehicle armor and through sheer weight of attacks and armor negation can bring down monstrous creatures. Maxed out Spyders can inflate the unit by up to 9 bases each turn, and with that many bases they can deny areas to deepstrike in and have the mobility to reach your back lines quickly. The quickest way to take them out is with Strength 6, the soulgrinder's mawcannon, or with many attacks from a demonette unit.
A note, Flamers of Tzeentch/ Breath of Chaos will not be very effective against this unit since the scarabs have 3 wounds each.

Canoptik Wraiths are Jump Infantry, have 2 wounds each, and have a 3+/3++. They can and will have purchased the lash whip equivalent so that they can strike before anything in base with them. They are Strength 6 with rending, but at T4 they can be beaten through numbers or double toughness.

Though at the same each wound inflicted become 2 wounds due to the vulnerability to blasts and templates rule, and you must remove full models when ever possible.

I thank the 4 that wraiths no-longer have WBB, as I have a HOK and 5 bloodletters put on 7 wounds on a wraith and it didn't died.

LiSharpeleo completely agree with scarabs they with destroy every vehicle they come across, nothing is safe. unless you assault them or shot the hell out of them. S6 for the win.

I agree with alot of these assessments. A couple additions. You can get Mindshackle scarabs on overlord and lords. You can take a royal court of up to 5 lords for every hq option you take. lords can be split off to units and as mentioned above, act as upgrade characters (not ICs). So a necron army could contain as many as 12 models with scarabs, scattered all over the place.

While the demon walker is immune to them, it is highly unlikely that it'll get into assault for a number of reasons. Scarabs are the most obvious as previously described and also it is worth mentioning that they are beasts, so they are fleet and get the enhanced assault range. The spyders can add bases to existing units and the only restriction is it must be in coherency. So spyders at the rear of a unit can add their bases 2" in front of the unit. This can effectively add like 4" to its already stupid long effective assault distance.

The other reasons are tachyon arrows and warscythes. Tachyon arrows are one shotter guns that are pretty much vehicle killers with max str and the best ap. Warscythes are pretty much chainfists assault weapons as well with enhanced str and 2d6 penetration. So even if you get the walker into melee, any warscythe models that get to attack will likely land a few glance/pen hits. Not to mention the command barge that allows lords to just fly over units and make assault attacks against it with a warscythe. It'll sting pretty hard to see your grinder wrecked in your enemies movement phase :P

The Mindshackle Scarabs are something that, thanks to the people over at MiniWargaming, anger me.

The rule reads:

Matt over Miniwargaming uses this to mean that a character will attack himself, be it an independent character, monstrous creature, or whatever.

Nowhere in this description does it say that a character will attack himself.

That text is what makes you hit yourself. It doesn't say explicitly that you attack yourself, but it says you attack your own unit. In the case of independent charactesr and most monstrous creatures, they are the only model in the unit they are hitting and thus you are required to allocate wounds to that lone model.

I think you've ignored the part about the allies.

Nowhere does it say the model will attack himself. He attacks allies. If no allies are around to hit, then he does nothing.

The text states he "inflicts 3d hits on his own unit". That line is the actual effect of the rule and fits into the standard rules for assaults. The model inflicts 'hits' (a game term) upon his own unit. You then take it from there using normal game flow. I inflice x hits, I then roll to wound vs avg toughness and get Y wounds. I allocate Y wounds to models in that unit (1 per model until all have a wound, then you stack them). IE if the unit has 1 model, it takes all the wounds (and thus the model effectively hits itself).

The preceeding line that you are refering too "If the test if failed, the victim strikes out at his allies." is descriptive text that doesn't translate into the game rules. There is no official definition for 'allies', and the line following this one (described above) contradicts the idea that you only attack friendly models and not yourself (wound allocation forces you to apply them to the attacking model if # of wounds equals/exceeds # of models in the unit). So from a RAW perspective, this means the line you are referring to is just descriptive text and not actual rules text.