Lightning Field — 25 points
Powerful arcs of energy link the Necron Lord and any unit he has joined. For every wound inflicted on them in close combat by an enemy unit or independent character, a single Strength 3 hit (with no AP) will be struck back as they are burned and shocked. The return blows are calculated after all other attacks are resolved and will hit the enemy that triggered them. For example, if one attacking unit inflicted three wounds they would therefore take three hits in return.
Errata — Chapter Approved: Codex: Necrons Q&A (v2.0): The Strength 3 hits are triggered by failed Armour saves that cause wounds, not directly by the wound rolls themselves.