The Dol Guldur Pikemen come from the Hill of Dark Sorcery to serve Mordor and have been given weapons induced with deadly poisons. They can only be trained at a Dol Guldur Fortress, which can be purchased for 2500 at an outpost plot. They are a late game substitute for regular Orc Pikemen but are mass produced slower due to the limit of outposts that can be built. Even though they have the same armor their poisoned weapons render them more effective against other units (but they are still weak to Mass Slayer Heroes).
Crack the Whip (with Orc Overseer) - For 30 seconds deal twice the damage against Cavalry and slows them down twice as much units but lose 25% armor
The Dol Guldur Pikemen can be given the following upgrades:
Orc Overseer - If paired with an orc overseer they will gain bonuses and the ability Crack the Whip
The Dol Guldur Pikemen are simply an attack upgraded version of the standard pikemen and therefore can be better utilized. However, they are present in a short supply since they are limited by the number of outposts, but if joined with standard pikemen they can prove to be very deadly. Other than that, the advice stays the same, in the extreme-late game they can be paired with the other Dol Guldur units and overseers to form a deadly force once well micro-managed. They are still on the same level as pikemen simply they have better attack therefore they have the same weakness and the same strength in their numbers. In addition Dol Guldur units have poison blades which cause them to poison enemies, dealing double damage and poison damage over time.