This is a mod for HALO: CE included in the MCC. I found it on the workshop page and gave it a go.

Its a small self-contained single player campaign set in the Resistence: Fall Of Man setting.

I don’t really know much about those games outside the basic premise, but visually it looked close to what I remember of the official games. There’s all new weapons, enemies, and friendly NPCs. The mod even has some setpiece battles.

I appreciate the work that went into all the new assets. The friendly NPCs especially could have been left out, but the mod maker really committed extra effort by including them.

There’s even a driving section near the end with a remodeled Jeep (though the UI still calls it a Warthog).

A fun diversion for an hour or so to beat it.