For 5 years? The dude has no friends and no hobbies and it takes him 5 years to make up the Special Beam Cannon? I wonder how long it took Krillin to make the Destructo Disk.
I mean, he trained for 3 years after hatching to fight Goku, but he was physically a kid for a good chunk of that time and probably needed it. Taking 5 years to wait to fight your rival that you're on par with is silly.
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