Nail will give you missions every now and then. The game says if you skip a mission you can miss it, if one pops up do it if you can about these missions.
Nail Mission 1 – This mission is to collect the Dragon Balls. You don’t have to defeat the enemies but it will make the mission easier. Turn them all in to the ship and you will beat the mission.
Nail Mission 2 – Another mission to collect Dragon Balls but this time 4. There isn’t as many enemies this time so it is easier to just defeat them.
Nail Mission 3 – This randomly popped up as I was doing instructor missions and, surprise surprise, you need to collect more Dragon Balls. This time it is Zarbon leading the assault but again, only 3 targets. Take them down, grab the Dragon Balls and finish the mission.
Nail Mission 4 – Another Dragon Ball quest from Nail but this time against the Ginyu Force. Can’t really avoid fighting in this one, Nail get smoked eventually and all the bad guys attack you.
Nail Mission 5 – Another Dragon Ball quest from Nail. This time you face Raditz and some Saibamen. You know the drill by now, take them down and grab the Dragon Balls.
As you can see all of Nail’s missions are to collect the Dragon Balls. Each time you do it Nail will start to trust you more and more. Eventually, he will let you see the Guru and he will unlock your potential letting your stats go from 100 to 125. I am doing his missions again to see if you go to 150 or not, check back soon for an update.
After you do do the mission to recover 7 Dragon Balls, it will reset and you have to get 3.
When you see Guru a second time he will give you a Time Distorted Egg and if you see him a third time he will give you a choice of some Wishes. I think it was Super attacks, more power, food, item and maybe one more.