These are things that simply add value; the main fun is found in the game's single-player campaign.

There's no plot to speak of, nor is there a single-player campaign.

So why am I still thinking about it after having beaten the single-player campaign?

Halo's single-player campaign was nothing to write home to Earth about.

The game is made to be played online, with the single-player campaign used for training.

The player takes on the role of various characters during a single-player campaign.

It was later revealed that the game will have a single-player campaign.

It was then further delayed until June 2011 to allow more time to work on the single-player campaign.

Many things available for the single-player campaign, are also added into multiplayer.

Only the single-player campaign is available hence the name of the edition.