OK if you know you are going up against Necrons here are some things to consider.
1) Kill the destroyers first 36" guns while all the troops guns are 24" rapid firing. Remember destroyers move likes bikes (12-24" ) and will get a +3 invulnerable when they move over 18".
2) Take at a min 2 ravagers one with 3 darklances and one with 3 destroyers and give them night shields. I would recommend 3 ravagers 2 with 3 destroyers each however I like the talos to take out guys in HtH as well.
3) If there is a monolith you will need to dedicate 2 foot slogging with 2 darklances in each squad at the min each round and move the rest of you troops away. It is slow after it deep strikes use your speed. However it is BRUTAL vs DE.
4) Take more agonizers than normal wounding on 5s is hard so take the hit and add 2 more to the list. Killing necrons in HtH with normal troops is very hard get the Arcon or witches to assist in a charge ( pre plan ).
5) The scarabs move like bikes and ignore terrain so they will be boosting 24" a turn to get to one or 2 of your squads and tie them down you will need 3 squads to deal with 10 (30 wounds ) scarabs in 2-3 rounds and they are fearless.
6) I would also go Raider heavy on troops so you can boost troops away from a deep striking monolith.
Pick squads and try to wipe them out with concentrated fire if none are left standing most of the time there is no WBB roll.
