Golduck is one of the most versatile Pokemon in the tier. It sets a standard for Speed in the tier, with its base 85 Spe being a key tier to outpace. Its Scarf set is an excellent revenge killer, especially for the many weather sweepers of the tier, due to its decent Special Attack and Cloud Nine ability. With a Scarf, Cloud Nine Golduck outspeeds every Chlorophyll and Swift Swim user in the tier, like Jumpluff, Mantine and Leafeon. It can run a potent Life Orb All-Out Attacking set, or a Calm Mind set meant to sweep late game. It is notable that even without a Scarf, it can outpace quite a large amount of weather sweeprs and hit them back hard with Ice Beam and Hidden Power Electric. It has Encore to disrupt your opponent's set up as well, providing plenty of time for your own set up. It functions extremely well in the Rain due to Swift Swim and its excellent coverage. While Simipour may seem to be better with higher SpA and Spe, it is not as effective against the weather teams that PU contains; nor can it boast the ability to blast holes teams with a single Rain Dance. Ironically, it is one of the few Water Pokemon that can function in the Sun as well, thanks to Cloud Nine negating the Sun's negative effects while it is in play. It can also take advantage of its usable bulk with a bulky Calm Mind set to power through teams while with multiple boosts. This means that Golduck is very easy to fit on most offensive teams, and even balanced and defensive teams can consider using it as a win condition. With its ability to perform is so many different roles successfully, as well as being a decent defense against weather teams, Golduck is without a doubt an S-Rank Pokemon.
Yeah I've been really busy the last year, like no time for Smogon at all really. But things are easing up a bit and I have summer to look forward to! So yeah I thought I might pick it back up. Really good to hear from you again, hopefully we can have some fun battles soon! I just lost to a Sunny Day Charizard though so the team defo needs work lol :P
I only get to play with Don, so I'm not that well versed in PU. I do agree that Combusken is a very potent Pokemon, especially in a tier with so many weaker Pokemon on the Special side. If I played more, I might be able to confirm it or not, but no one ever seems to play PU when I go on Pokecommunity or Joim's servers.