Pokemon Diamond - Obtained four gym badges

For the first time in Pokemon, I am stuck. It isn't that I don't have things to do. I could explore the underground some more and get more interesting items like evolution stones. I could work on leveling up and evolving my pokemon. I could try to breed pokemon with interesting attacks. All these I can I do. What I cannot seem to figure out how to do is advance the story.

I like that, in Hearthome city, you can't immediately battle the trainer there. It is a nice way to set up for later. Also, this then exposes two possible paths to take. I ended up taking the one that heads North and thus encountered Veilstone city first. This was great because it allowed me to defeat the gym leader and use the Fly HM. Fly is equivalent to the Return spell in the Dragon Quest (Dragon Warrior) games. You can return to any town you have been to before. This makes doing things like checking the global trade station, picking berries you planted, and retrieving Pokemon in the day care much easier. It really seems like the designers went out of their way to take any tedium out of this game and just let the player do what he or she wants. The only thing left that sometimes annoys me is random encounters, but I haven't tried using the item that decreases them.

So I then headed to Pastoria city. I played around in the Safari zone. It is a neat concept - a new way to capture Pokemon. It can also be a bit frustrating if you are trying to catch the pokemon that are unique to it. When battling pokemon in the wild, you can get near assurance that you will be able to capture it. Since, in the Safari zone, there is no way to weaken or affect their status. All you can do is throw things at them. That makes them more likely to be caught, but also more likely to run away. Nevertheless, I caught just about all of the pokemon unique to the Safari zone (I'll get you some day, Azurill!)

Anyway, after defeating the Pastoria gym leader, I am stuck. I am sure I have to make use of the new Defog technique. I am also pretty sure I have to get past the Psyducks. But I cannot figure out how. It looks like I may have to consult an FAQ.