There's been quite a lot of discussion on ball matching here lately, and lots of repeat questions, so I thought I'd give a quick PSA on the topic:
Finding the right matching Pokéballs is not too difficult a thing to accomplish on your own. There's a few things I consider when picking the ball of a Pokémon I'm about to breed:
1. The color scheme of the Pokémon
2. The theme of the Pokémon
3. The rarity of the ball
4. How common a specific ball/combo is around Smogon
For example, let's consider Gastly. Gastly and it's evos are purple in color, so the first thing to do is obviously find if there is a purple Pokéball that is passed down for breeding. (Here is my favorite source:
http://www.serebii.net/itemdex/list/pokeball.shtml). As you can see, only the Masterball matches Gastly in terms of color scheme, which regrettably does not pass through breeding.
Next, let's consider the theme of the Pokémon. Ghosts are creatures of darkness, so the most logical choices are the Dusk and Moon Balls, giving us multiple options. At this point, many people turn to the Simple Questions/Requests thread to ask for opinions. A good idea, but let's be honest, I can't be the only one here getting tired of seeing people ask what ball fits Kangaskhan for the umpteenth time, right? So let's continue on.
Rarity. The Moon Ball is only available in 4th gen, while Dusk Balls are available in 4th, 5th, and 6th, making the Moon Ball technically more rare, since less people have access to it. At this point, it would be perfectly logical to conclude that the Moon Ball is Gastly's best fit.
HOWEVER, if you look around many of the shops on Smogon, you'd see that Moon Ball Gastly are EVERYWHERE. Really. You can't not find one. So, chances are if you breed one, you won't get many offers for it. Though it's a close call, I'd have to say that the best ball for Gastly in the current state of affairs on Smogon is the Dusk Ball. This gives you the perfect combination of all 4 factors, and gives you something somewhat unique to offer in your thread.
This thought process can be applied to any Pokémon, and has served me well as I expanded my shop's selection of matching balls. I hope that some people find it useful, and that it helps cut down on some of the repetitive ball-matching requests in this thread.
