Throw it on the ground and tell her you won't be a part of her system.
Or just do the reasonable thing and exchange it for Halo 4(if it's still in the wrapping). It's not like mom's generally know what they're doing when it comes to games, I doubt she will be offended. --- Gamefaqs: The most passive aggressive place on the internet.
if you haven't opened the plastic yet, you MAY be able to trade it for Halo.
this is probably the part of me that hasn't yet given up on humanity talking though.
Yea i know I can just do that but I feel likes its rude to say yea thanks but I wanted halo I can trade it in because she did buy it for $60 so at gamestop unopened games can be traded in within a week but I don't want to be rude to my mom --- My name is a secret because... It's just cooler that way