There is also the possibility that Ken had his hair radioactively dyed. I mean really, that hair is practically glowing.
I used to tease Sarah in the past for the way she would accidentally draw characters' fingers in the shape of bananas, but in this comic her banana drawing skills were essential.
I'm not sure what the developers were thinking when re-designing Ken - I like the update to his mechanics, and even his clothes, but the hair is just...you know what? Nevermind. It's fine. This game is ridiculous, and not just because of Necalli (whose hair is basically snakes) or F.A.N.G. (who is, in my head canon, Waluigi's Chinese cousin). Let's just assume that Ken is simply in the process of achieving Super Saiyan Bananas, in order to fight Necalli, who is in the process of achieving Super Saiyan Snakes.