OP, if you want a multiplayer only game there are about 20 of them between Battlefield and COD that you can choose from. if you want an open world game for Halo, they already did that. It's called destiny. The story is what makes the game, I love the multiplayer as much as anyone else but I wouldn't buy if there wasn't a campaign, in fact I think they spent so much time on the multiplayer that the campaign for H5 wasn't as great as it could've been.
Multiplayer ONLY Halo game?