Is it Illegal to Play WoW on a Private Server?

It is not illegal to play World of Warcraft on a private server. No one has ever been banned from retail for playing on a private server before. It is not illegal to play on Project Ascension WoW. It is not illegal to play on Warmane. It is simply not illegal to play on a private World of Warcraft server and you will not get in trouble for doing so. You can keep your official Blizzard account safe by not advertising the fact that you play on emulated servers in-game or on the forums.