The Grumpy Old Guy was a character in Custom Mod Adventure: Delivering Mail with Craig. He was the last person who DanTDM and Craig had to deliver mail to. However, there were Iron Bars around his house with a sign that said "NO MAILMEN", which is really stupid. Dan made a plan to get the package into his yard, which was using an Item Cannon. However, when Dan and Craig launched the package, they found out that it was filled with explosives, and it blew off the side of his house. Dan and Craig made their escape. It is unknown if he survived or not.