Hello there, im wondering if anybody knows the best price to get halo CE Amazon have it used for £4.00 but I don’t know if you need a key ? if anyone can help me out its much appreciated want to play this epic game again 
you need a key but i don’t think it needs to be activated online, it can be used as many times as you want, hence why I’ve been able to install it over and over again
Get it for PC if you can. You won’t regret it.
Here’s a copy of CE on eBay for £7
It’s a shame you couldn’t buy it when the money actually supported Bungie.