Tactics against Necromancers.

Hasted units can be a problem. And Necromancers almost always have air magic. Only slowing spells are effective against them. Hasted skeletons can reach you in two turns, which is very dangerous. But when playing against Necromancers, you shouldn't focus all your attention on the skeletons (this is a mistake many players make). It's better to use area-of-effect spells, even if they deal less damage.