Mephisto fellers, the boss in the third act of Diablo II, is called Lao Mo for short. Because brushing this Boss is faster and simpler, I often lose some practical equipment, so it is also commonly known as a model worker.
Mephisto fellers technical Demon and other additional notes:
Model worker's trick: poison nova; Lightning; Live bolt; Dark ice (although the original is a "skull" monument, I prefer the name-translator) comes from the wilderness of Baili.
It's best to clean up the monsters like senators (poor translators) nearby before fighting the model workers. If some guys are really difficult to deal with (for example, those who are physically immune+ineffective in ice system, and those who are strengthened by lightning+multiple shots), then you can try this trick: open a portal in the room in front of old M or on the left, and then lead those lame people who can't handle it to the stairs on the second floor of the Hall of Pain. Run up the stairs (bully us disabled people-the lame), return to Kurast port from the station on the second floor, and then return to the third floor from the portal. If you successfully distract the cripple and open the door far enough, the cripple will wait at the stairs. Now let's go one-on-one with the model workers!