Her name is an anagram for Devil, and her last name is Satan. Videl is more metal than you. She is not on the list because she was a badass even as a normal human, or because she popped Gohan's cherry, no she's on the list because she did the one thing any of us would if they found out people like Gohan and Goku existed - SHE ASKED TO BE TAUGHT HOW TO USE KI. Being one of the best martial artists in the world and being the daughter of the World Champion himself means little if you can't fly or shoot laser beams out of your palms, so she told that nerd Gohan to STFU and show her. After that, she doesn't really matter unfortunately; she shows up to contribute to the worst part of the show (The Great Saiyaman), get her ass kicked by Majin Goons, and pop out a baby. If any of us could take her place, wouldn't we?
Were this a list of strongest DBZ characters, Roshi would be at the bottom just above Yajirobe. Lucky for him, this list is not about power levels -- it's about those characters that stay with you long after the show concludes and you reach an age where you finally start to "get" the things that went over your adolescent head. Like, for instance, Roshi basically being every guy currently being outed in Hollywood as a creep. Yeah I'm not going to lie, as much as the "lecherous old man" trope is a mainstay in anime, it doesn't make Roshi's antics any better, especially decades later. That being said, you can't ignore the geezers better qualities; he did, after all, train some of the strongest beings on Earth, and did it in a way that didn't turn them into complete assholes (like Tien and Chiaotzu's original master). He was an even better character in the original Dragon Ball, as one of the strongest and most respected fighters in the world despite his advanced age and proclivity towards underage girlsUH I'M JUST GOING TO MOVE ON.
Who's got one thumb and is the only good incarnation of Gohan? This guy. A life of constant battle has turned the alternate timeline Gohan from a shy bookworm into a straight up asskicker and mentor. He never reached his full potential in this timeline as Android 17 and 18 killed most of the Z warriors, and he was most certainly still a virgin at the time of his death (that sucks), which only makes how long he lasted all the more impressive. If it wasn't for Future Gohan, we would have never gotten an even GREATER character...
He arrived out of nowhere, a kid with odd fashion sense and a purple mop-top that wielded a sword at a time where every character could shoot nukes out of their hands, and made a mockery of Freiza and his enormous father. As the Android and Cell sagas went on, he proved himself to be a powerful character, but even more importantly a SMART one. He had Vegeta's strength and pride, but without the dangerous ego that lead his father to make mistakes; knowing the terrible power of the Androids, and later Cell, he bid to make NO HESITATION in killing them for good. If Vegeta didn't get in the way, Future Trunks would have saved the world from the following catastrophes - all while having the best Super Saiyan hair in the series.
Krillin: "Th-that's impossible...! Wh-why can he become a Super Saiyan...?! Don't you have to have a tranquil heart to become one...!?"Vegeta: "I was tranquil...Tranquil and pure...Pure evil, that is...
Back when becoming a Super Saiyan was still a rare and awesome feat, seeing Vegeta pop out of nowhere to save Goku and absolutely demolish the dangerously strong (and ugly) Android 19 was as unexpected as it was HYPE.
Being cocky actually worked in his favor this time as he was able to send a strong foe (Dr. Gero) off running until he could eat a senzu bean and get his energy back. Juxtaposed this to Vegeta going Ascended Super Saiyan against Semiperfect Cell; Vegeta HAS the power to get rid of Cell right there, but his ego inables Cell to absorb Android 18 and achieve perfection, quickly surpassing Vegeta's power and putting literally the entire glaxy at risk. When Vegeta returned to Earth in the Android Saga with the golden up-do of a Super Saiyan, he reclaimed his title as the biggest badass in the universe. Well, the biggest badass on Earth anyway. Well, the biggest badass on Earth that was not in a state of suspended animation. LOOK HE WAS COOL OK?
That's right, Goku just barely cracks the top 5. Still, Goku is legitimately a great character and there is a reason he is the posterchild to 90's shonen anime nostalgia; an innocent and pure heart encased in hard muscle that makes friends of enemies after punching the everloving fuck out of them. He was a natural talent, even by Saiyan standards, but he constantly pushed himself to improve for the thrill of the fight and to save his friends more times than he can count. He was the ripped manchild every 13 year old wanted to be, the anime Superman ideal no amount of "power up" yelling in your backyard could come close to. Why not #1? Because just like Superman he is a little TOO perfect to be totally captitvating.
Your green dad, the demon with a heart of gold and 7 swinging balls. Pretty much the entire Z Squad started off as at least rival to Goku in one way or another, some friendly and others deadly. Piccolo is the later sort of ally. We catch up with him at the start of Z as he is minding his own damn business meditating in the arid wilds, interrupted by a Planet Flipper because his Google Glass told him Piccolo was one of the strongest beings around. He ALMOST was, anyway, and remained ALMOST the strongest for the majority of DBZ - and when you're not a Saiyan, that is pretty impressive. Beyond just strength, the unique abilities of Piccolo as a fighter ranged from a mastery of high powered ki attacks, a mind for battle that was seldom rivaled, to the distinct physical propeties of his alien race. A stoic and calm courage gave way to a caring parental figure that was a better father than most dads, despite reproducing asexually through barfing up eggs.
Being noseless, half everyone's size, and having pitiful Earthling genetics never stopped Krillin from joining the fight and helping his stronger allies. When not even Goku and Vegeta could save the Earth from Kid Buu, Krillin charged the little pink shit without hesitation - not because he thought he could win, but because he had to try damnit. This is made all the more important when you realize that this is taking place in The Other World when Krillin was already technically dead, meaning if he were to be destroyed by Buu at that time there would be no way to bring him back. Does my man care? Hell no. When you're married to the hottest robot this side of Bicentennial Man you gotta at least try.
It's true that Power Creep has made Frieza a pushover in hindsight, but Dragonball Z has never done a villain as well since. The pathos of his character and his immediate connection to the protagonist(s), not to mention his absurd power at the time, made Frieza the ultimate anithesis to Goku's journey. Frieza wasn't some Villain Of The Week, nor was he cooked up in a lab by a gereatric cyborg; his greasy tendrils reached all the way to the very beginning of DBZ, pulling the strings on the Saiyan threat that was our first taste of this suped up version of Dragon Ball. His backstory wasn't SUPER creative, but it established him as an infamous universal oddity - a self-proclaimed ruler that used fear as a means of control, and has been doing so for decades at least. On Namek, his presence in the periphery of Krillin and Gohan's quest built up his reveal as an unstoppable and malevolent force, until the totality of his evil was explained by Vegeta in an emotional confession that put the lives of previous villains and heroes into perspective. Frieza was the most important, overarching villain of the franchise and NO, MECHA FRIEZA DOESN'T COUNT.
YES VEGETA IS ON THE LIST TWICE, DEAL WITH IT.
By the time the Buu saga kicked off, Vegeta was a father and an ally to the Z Crew, betraying his initial introduction as the evil prince of all Saiyans. He was as frustrated by his civilized nature as we, the audience, were, and longed to return to his brutal beginnings. When Goku showed a flash of his hidden power in his fight with Yakon, Vegeta knew it was unlikely he would ever catch up to Goku's true power - until, a shortcut presented itself. Babadi took over Vegeta, anchored to the hate still present in his heart, and lifted his power to contend with his long time rival. The evil finally returned and took over Vegeta, who gleefully murdered a hundred or so innocent bystanders, and one of the best DBZ fights of all time was underway.
BULMA: The smartest person on the show, if not an insufferable loudmouth.
YAMCHA: Doesn't deserve the hate he gets (even if he is one of the weakest of the Z Fam, that still makes him stronger than 99.9999% of humanity), and gracefully bows out when he knows he is no longer relevant.
TIEN: A few good badass moments, but otherwise an unremarkable story after the Saiyan saga.
MYSTIC GOHAN: A great idea, and it was cool that he was the strongest non-fused character at that time without needing a Super Saiyan transformation, but he got punked by Buu immediately.
SSJ2 GOHAN: A cool transformation and a satisfying end to the build up of him being the strongest character, but he needs his dad to bail him out in the end because he's a cocky twit.
YAJIROBE: The person we would be if we existed in the Z universe.