Walton's Gold

 is a multi-player co-op mission included in the Outlaws To The End DLC for Red Dead Redemption.

Walkthrough
You start at the far end of the camp in Gaptooth Breach. There are a lot of miners around, but the three most dangerous are the gunners that will rush to the Gatling Guns (left of the mine, and above the mine), and the big, fat, bearded fellow with no shirt who will throw dynamite at you (there may be two of these enemies however there is usually only one). He runs back and forth across the mine entrance. At least one marksman is extremely helpful for taking out the gunners and the bomber.

Once inside the mine, you only have 5 minutes to collect the gold and get out. The mine cart is located in the main chamber, and the gold bags are strewn throughout the mine. You can carry two bags at once, so grab two and get to the mine cart, rinse, repeat. You need at least 10 bags, but you can grab as many as you want (more bags means more exp). Once you have ten, reinforcements spawn inside the mine, so take them out while one person (probably the Marksman) moves the cart and/or grabs more gold. When you hit the one minute mark, forget the gold and get the cart out fast.

As you wheel the cart up to the surface, you will be forced into the nearby building as one last wave of Walton's Gang attempts to stop you fleeing with their gold. Shoot them down either with your basic firearms, or with the Gatling Gun situated near to the mouth of the mine. Once all remaining enemies have been taken down, the mission is complete.