Necromancer

Necromancers distance themselves from their opponent, shoot a distance poison attack and summon undead creatures. They shoot you more if you stand close. Necromancers have really valuable items in their loot: Boots of Haste and Skull Staff. They have a weak defense so even knights are able to kill them with a little limitation: their Death Hit works only if you stand next to them which means you will lose a lot more hp.

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Strategia

If you hunt them in Drefia you might want to lure all the Revenant which spawn between the rooms to the top right corner where the Sheep spawn. You will need a Stealth Ring.

Strategia — mag

Mid-level Mages can summon 2 Revenant to kill Necromancers in Drefia, the most common place to hunt them. As a high-level Mage you can hunt these great with Great Fireball Rune. Rush into the rooms so you can hit all of the Necromancers at once. As soon as your Energy Wave usually hits more than 580 you can also use E-Wave to oneshot them.

Strategia — łucznik

Archers should use Bolt+Heavy Magic Missile. Knights can solo these but it is not recommended as their damage is a lot higher in melee range.