Yo peoples! Im here to assist. I wouldnt reccomend Gyarados unless u want a physical sweeper. He makes a bad water type sience water types should focus on special attack. As a water type, I would reccomend Lapras sience it has good special attack,special defence, and HP. Also, it can learn electric type TMs. Also, I suggest catching a Ghastly, later evolving it into Haunter and, if u can trade it, Gengar cuz it haz great special attack and decent speed. Also, it can kill pesky psychics but watch out cuz its a poison type. Thats all for now, but i hope u put those too into consideration cuz i use Lapras and Haunter on my game and they've never let me down before.