Hidden Conditions
First you have to face Raditz and his Saibaman partner. Take care of the Saibaman first since it will continously annoy you with consecutive Ki Blasts.
After taking care of them, you should be going to the industrial city. Before doing that though, make sure to search the area for a random Time Patroller. This one is quite powerful but if you manage to defeat him, you'll get a Hercule Badge, and possible a Dragon Ball.
Once you reached the industrial city, you'll have to face Nappa and his Saibamen. Like before, take out the small fries first before concentrating on Nappa. After defeating him, you can find Yamcha in one of the city streets. (Use the search function to find him). If your HP is critically low, you can talk to him to recover your HP a bit.
After that, head to the Capsule Corp gate and face Vegeta. If you manage to defeat him quickly, the battle damaged Nappa and Raditz will back him up. He'll also get back to his feet and fight again. Defeat the three of them to complete the mission.
How do i get the "im the strongest on earth" z-soul
How do I get the vegeta body armour?
its rng when you kill vegeta