Well that's ABSOLUTELY HORRIFYING

Summary
After a conversation with Bob and Wade about things they've tasted and licked, they start the game by using an old save and see that the house they built in a previous episode has a spot where a fireplace was marked to be built. Mark climbs up and enters the house only to find the backdoor blocked by a wooden wall. He eventually tries to destroy the wall, but accidentally demolishes the whole tower in the process, leaving only a small deck and the ruined wall blocking the back door. The three of them decide to build a new structure and eventually add-on to the stairway that managed to survive the tower's fall connecting their base to the nearby cliff above them.

They continue building their new structure well into the next day and decide on constructing a new large platform. While they're gathering the needed logs, one of the trees that Mark was cutting down earlier falls on him. While Mark is away, Bob is attacked by a large six-legged creepy mutant called Virginia who ambushes the group out of nowhere. Bob and Wade hide at the base as Mark comes down and the three of them try to kill Virginia by luring it into one of the Happy Birthday traps set up in front of the base. After a brief confrontation, the mutant is defeated and its body is carved up to create new armor, much to everyone's horror and disgust.

Later on, Mark constructs a bridge on the nearby river so that the group can collect logs on the other side, but the bridge is destroyed by a falling tree and has to be rebuilt. Bob helps Mark create a new bridge. At night, while the bridge is being constructed, a mutant attacks the two, but is unable to cross over due to the incomplete structure. The bridge is eventually remade and is used for transporting resources. Not long after, the mutants attack in a group and start using the bridge to cross the river. Mark and the others flee back to their base, but the mutants follow them and end up destroying the middle door, as the video comes to a close on a "to be continued" caption.

Quotes
"Oh yeah, you know what, this bridge really does make it possible for people to go on."

- Mark after a mutant uses the bridge to attack the group