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yes they do IF the lord makes his role and there is a unit of necrons "alive" within 6" or on the table and a spyder within12" of the deadun`s or a monolith within 18".
This is a controversial topic. I initially would answer yes, because the Necron Lord is still in play. This can be argued one way or the other and upon further contemplation the answer is "no". The way I came about this was by asking the question: does Gaze of Flame still work for a Lord that is felled? The obvious answer is "no".
Furthermore, a Monolith has no ability to grant WBB to model or position them in range of a RO, it only allows re-rolls for those models that can already roll for WBB by using its Portal. Once again, the nuances are important. You cannot teleport a squad of Warriors, all killed by PWs, into range of a RO and expect them to get WBB rolls. Either they were in range at the time they were felled or they weren't, the FAQ makes this clear.
Check out the LO Necron FAQ for more explanation.
Karmoon: "well.. any kore = good kore" 12:35pm PST 23 May 2007