how to play halo MCC offline

Hi, I hope you're doing great out there. I am an Independent advisor and I am here to help you with your concern.

First, make sure that your account is set as Home Xbox on your console by following the steps below:

"1. Sign in to your account.

2. Press the Xbox button to open the guide.

3. Select Profile & system > Settings > General > Personalization, and then select My home Xbox.

4. Check "Make this as My Home Xbox"."

Once done, set your console to offline:

Settings > General > Network Connection > Go Offline.

For your reference, you can check this link: https://support.xbox.com/en-US/help/hardware-ne...

I played and completed halo mcc offline, none popped at the time but when I connected back to live one by one all 60 achievements popped

As said, if you are talking about MCC is a thing. But ‘legacy’ in the halo games means Halo CE, 2 and 3, on the original consoles. So the first xbox and the 360. If that’s the case, then you should be totally able to play it offline.

The original xbox one console is the one from 2013 or the FIRST from early 2000s?

I don't know if you are playing MCC: Halo 2 on PC or console. here's a link to change your video settings on PC.

https://support.halowaypoint.com/hc/en-us/articles/360040626111-How-to-Change-your-Video-Settingsi would also
make sure MCC is updated on the device you are playing it on. if you don't know how to update MCC on PC here's a link to do that.

https://support.halowaypoint.com/hc...dating-Halo-The-Master-Chief-Collection-on-PC

I wonder how big of a download/installation Halo: MCC will be?