Best Case Scenario
He stood still as he glared at the moon, wagging his tail back and forth as he enjoyed the view of the full moon for the first time. His eyes shrank in size as his excited expression was soon replaced by a mesmerized one. His skin became pale and his tail motionless as his heartbeat decreased to a stop. He stood still for a couple of seconds as his heart began beating with heavy pulses, unleashing the Saiyan inside of him as he transformed to a Great Ape.
He began destroying everything in his sight as Piccolo tried to understand what was going on. Luckily, he recalled something Raditz had said and came to the conclusion that the key to the Saiyan's power was in the moon, so he destroyed it, watching Gohan as he transformed back into a human shortly afterwards.
As Gohan lay naked on the floor, Piccolo figured blowing away the moon was the right thing to do.
'Maybe I should pull out his tail, too.' he thought. He pondered on the idea for a while, but he figured, 'Well, there's no need to worry about him transforming like this again. And now that we know their tails are a weak point, I guess we could use that to our advantage if things ever came down to it.'
He looked at the vulnerable kid lying on the floor and though, 'I suppose he's been through enough today. The last thing he needs is to find a fundamental part of himself missing when he wakes up.' He extended his arm, using his powers to give him some clothes.
With that, he left.
Gohan woke up to find himself down from the cliff he'd been staying in. He tried to piece things together and thought, 'Lets see, last night, I was looking at the moon, and then..' he undid his pants, pulling them down enough to take a leak as his tail kept his pants from falling down. 'And then, I don't remember anything.'
"Oh, well." he said aloud, pulling his pants back up and tying the belt around his waist.
'Huh? My clothes have changed.' He said as he looked at his reflection in the lake. 'Well, that's strange.'
Seeing as he was in the middle of nowhere and he had nothing better to do, he took his clothes off and jumped in the lake. He noticed some fish as they swam around and tried to catch some, but gave up shortly afterwards. He simply swam around, enjoying the water until he decided to look around for food.
'Boy, that was refreshing!' he thought as he got out. He looked around, finding his clothes missing.
Not knowing what to do, he got back in the water. He tried thinking back to what his father had once told him and remembered he could use his tail for fishing.
He caught a total of three fish and ate them immediately after catching them.
He tried to think back to something useful his dad might've told him, but nothing came to mind. Instead, he recalled a fluffy yellow cloud his dad used to use for transportation. He tried to think what it was called, but couldn't remember.
After a while, it hit him and he yelled, "Nimbus!"
Maybe it was too far for it to hear, so he called again, "Nimbus!"
It didn't seem like it was coming, so he sat down, thoroughly disappointed. 'Well, it was worth a try.' he thought as he found a shaded area for him to rest.
Out of the corner of his eye, he noticed a yellow line in the sky.
"Nimbus! Over here Nimbus" he called.
He saw it turn in his direction as he waved it down.
It stopped directly in front of him, so he climbed on and said, "Take me home."
It took him a while to find a place he recognized, but when he did, tears filled his eyes.
"Mom! Mom!" He said, jumping off the cloud as he ran towards Chi Chi, who was hanging up clothes to dry.
"Gohan!" she said, wrapping her arms around him as he clang to her legs.
Author's Note: Things from the show were shortened for the sake of the original story. Anyway, if you liked this you might also like another one of my Dragon Ball Z stories titled "Wish You Were Here".