Quote Originally Posted by Kaedan View Post
If it wasn't possible for someone to spoof your device and spoof you IP... which is actually is.
Spoofing an arbitrary IP for two-way communications is actually really hard. You basically need to have ISP-level (or maybe deeper) access to the Internet backbone so you can alter routing tables and have the traffic directed to you instead of the rightful holder of the IP.

Many ISPs give dynamic IP addresses to their clients, so if you're using the same ISP and are geographically reasonably close to your target (so as to be in the same address pool) it's possible to get the same address they used previously. However it's still damn near impossible to get just the right address at just the right time to take over the target's game account.