Do i need to be playing online to get the 100% game completion in red dead redemption? I want to get my last outfit, but it says to get 100% completion and i know how to get it. I have completed all the master challenges and story missions, along with the stranger tasks, but my completion is still only 98.5%. How do I get 100% game completion?
I highly, highly, highly suggest using the RDR Social Club, even if you just create an account to view the "100% Completion" page. The 100% completion page lists everything you need in order to get 100%, and if at any point you can get online for even a few moments, it will auto-update with the latest status from your game, if your Social Club account is linked to your PSN or Xbox Live IDs.
If you are missing an item, you can typically hover over it to get a quick tip as to what it is specifically that you need to do.
Failing that, you can use the 100% completion checklist on the Red Dead Wikia. It lists all of the things you need to do with links to Wikia articles on the best/easiest way to get them.
For reference, the things that count towards 100% are:
There's no requirement to be online, or to play the multiplayer mode for even a second to get 100%. Undead Nightmare has its own 100% completion award, and is tracked separately.