Halo 3 Co-Op Not Available Online?

The muliplayer co-op feature in Halo 3 might only be available in system link or split screen modes, as it seems Bungie are having issues getting it to work properly online.

Speaking to Electronic Gaming Monthly, Frank O'Connor had the following to say:

"We know that people want it and we're trying to make it happen. I think the biggest problem for us for online co-op is that we have a situation where you can be in a Warthog with five troops, almost a mile away from the other player. That's a significant challenge. And there's lots of design things you could do to prevent that from happening, but they would make it not feel like Halo anymore. If we can make it happen in a way that works well, we will - and if it works badly, we won't."

All hope is not lost should it not be included in the retail version when it is released though, there is always the chance it could be implemented via a patch update in the future.