Unown is like, the worst Pokemon of all. All it knows is ONE Hidden Power and it has pathetic stats. Magikarp is WAAAAYYY better than Unown. (Much to Nica's resentment, I actually do use Magikarp in competitive battling lol.)
Actually, Magikarp is a really good Pokemon and I was able to defeat (Nica's) Virizion by spamming bounce. Just give him the right item, max out the right stats, and you've got an epic Magikarp right in your pocket ball.
Also, Magikarp actually knows four moves: Splash, Tackle, Flail, and Bounce. Flail and Bounce are incredibly useful xD