Do You Need The Cd Key Of Every Wow Expansion After The First One?

Question:

I am about to purchase the wow original. My step-dad has all of the expansions. Can I use those to expand the one im buying?

Yep, you need all of the expansions,
burning crusade key(after patch 4.2, it disppeared)
wrath of the lich king key
and then cataclysm key
hope can help you, i recommend a site:
http://www.guy4game.com/world-of-warcraft-us/wow-cd-key/?aid=1891

i bought all keys from it, it is 6 years site. hope can help you. best wishes.

i suggest you buy a level 80 account, and then level to 85, you can play cataclysm, fast and cheap. all keys is expensive enough. hope can help you.