Yep buy every buyable helmet and u get it it's easy as that but never wear it on matchmaking u will get banned use it in custom games
Care to elaborate why you would be banned for wearing a helmet that is a part of the game during a mm game?
I second this as the only way you would be banned for going online with armor is if you used an ill-legit method to unlock something, such as modding, to unlock armor permutations that A.) You cannot unlock anymore (Such as the Eternal Armor Effect), or B.) Permutations that you have not met the proper prerequisites yet to unlock, and then go online to matchmaking with the armor you did not earn. If you do this, the banhammer is pretty good usually at catching that and will issue a ban to people who do this.
As long as you played the game properly and legitimately unlocked the Haunted Helmet, you should be fine. People might be jealous that you have said helmet and file false reports to the LIVE Enforcement team, but that will backfire on them.
