Acerac
Banned
I will probably drop some money on an adventure since they look fun, the question is which one haha.
How would one get comfortable drafting a deck?
Get the latest adventure first, it'll stick around in all formats for a very long time and has a ton of great cards included. Granted, all adventures are full of great cards so they're all strong investments if you want to spend money, but the older they are the sooner they will only be playable in one format.
At this point getting in to arena can be rather difficult if you're not practiced at CCGs, but heartharena.com can serve as a strong guide.