This is my take on what a competetive version of Mako's deck would look like. IK he didn't reveal having The Legendary Fisherman until Battle City. But I thought it would be better to introduce it now, because he does mention about his dad during this episode and a person like Mako would use this card in his deck. This would also be a fun way of taking control over the game, since Duelist Kingdom has a rule that duelists cannot attack directly and The Legendary Fisherman with A Legendary Ocean would be one more obstacle that Yugi would have to overcome during his duel with Mako.
Credit for the inspiration for this deck goes to, once again, The Retro Expert. His video is linked.