Man at the End of the World: Being Tricked into Slaying the Dragon at the Beginning

"Three years later, the giant dragon will destroy the world, and a breath of dragon breath will shatter the planet! If you don't want to die, level up quickly!" Su Han believed the system's words and worked hard for three years to master the dragon-slaying skills, just waiting for a decisive battle with the giant dragon. The end is coming as expected, open the door... There was no giant dragon covering the sky, just a group of slow-moving little zombies that screamed and screamed. Su Han looked at the dragon-slaying knife in his hand that could destroy stars, and was completely confused: "Dog system! Where is the dragon slaying we promised?"