HIVE

It looks like they use a custom model. You can download it here, I included instructions:
https://www.hiveworkshop.com/pastebin/98d0c9b3e5ef809009d0dd60143bc6b215602/

But I might recommend using this model if you want a really good looking Lich King ;)
https://www.hiveworkshop.com/threads/the-lich-king.154837/

Ummm sorry for not linking you the link of the model i'm using... here it is https://www.hiveworkshop.com/threads/lich-king.48593/#resource-21644

That model that you linked doesn't have the helm or the sword. The screenshot is wrong too.

Did you check the model I linked above? I'm pretty sure it is the one you are looking for. It has the helm and sword.

I have checked it but is different from the one i want. Also this model without helmet and sword was used at the last chapter.

Do you know how to attach files?

You can attach files by opening the "pastebin" (top of the site) and uploading a new paste. Then you can post the link here.

Anyway, I'm not sure how to help if that model isn't the correct one. You should look through the rest of the imports in RotLK and see if any of them are the one you're looking for. They might've used the helm + sword as attachments.

Here is the paste: https://www.hiveworkshop.com/pastebin/ccb138d729ef7f613fe515e4afd7e79715605/

i suggest that you also try to import it by yourself so you can clearly see my problem :)

Notice me senpai

So I opened the campaign, and it looks like he uses a custom model for the helm, weapon, and shoulders. Here is an example map, run it in game to see the model put together:
https://www.hiveworkshop.com/pastebin/ba462252583c0aac900ba01f6b053b6415611/

I attached the models using triggers (open the trigger editor to see), but you can also attach it using an item or ability:
https://www.hiveworkshop.com/threads/how-to-attach-a-model-or-an-effect-to-a-unit.7314/

THANK YOU SO MUCH YOU WONDERFUL PERSON!!!! Out of 8 STAFF members i asked to help me, you were the only one who can do it... I will never forget this. GOD BLESS YOU!!

No problem man, best of luck with your project!