Both Legion and the Battlechest are on sale once again, after they were just on sale last month.

https://us.shop.battle.net/en-us/fam...ld-of-warcraft
https://eu.shop.battle.net/en-gb/fam...ld-of-warcraft

Pro Tips:

1) You can have up to 8 retail WoW accounts on a single BNet, so if you have room on yours, you can spend $30-40 for a level 100 character boost since they're account-wide.
2) RaF has changed, so if you're looking for that sweet, sweet 300% experience boost, you're out of luck.