Depends on your abilities. I made the whole Castle pretty late, so not to lose my pyramids for a long time. I was in my 30er lvls. The steel skeletons in Iona's dungeon were hard. But you don't have to solve all lvls at once. If you have the quest from cat Arhu to free Z. you can try it if you want your pyramids back quickly. Freeing Z. is in an area where you can't use magic, but there are still potions, correct? After that you get the possibility from Z. to access the area where your pyramids are - 1 boss monster, mummies and liches. As soon as you have killed that boss monster, you can search for the person who has your pyramids and continue with all open quests.
Kiya
I'm a defensive gamer, so I don't like combat stress, being in my 30er lvls made battle easy. What is your lvl, please?