The Death knight appeared above the head of one of the trolls before the last one could understand what happened and pierced one of its eyes with the black spear. A blast of darkness was released inside the troll's skull along with a curse and the zombie horse kicked its face away, stone fists descending on the troll a second later.
Inside the death knight's ribcage, there was a teleportation crystal big enough to almost occupy his entire interior and he had been carrying the crystal since he started advancing, just waiting for the proper moment to teleport.
The evolved trolls were almost immortal as long as they were in contact with the ground and even having the brain destroyed would not be a fatal wound, but the curse that prevented the circulation of mana prevented regeneration and with half of the brain rotted, the troll dropped dead.