One of the most popular articles of all time on this site is the Four Pokémon you Should Consider article that Steve did a while back. This is a bit of a throw back to that, only this time we are looking at Pokémon that are made tons better because of a Dream World ability. My criteria for picking these Pokes was threefold:
1. They had to be Pokémon from Gens I-IV, in order to highlight Pokémon that have improved.
2. They had to be made exceedingly better due to their DW ability.
3. They had to be flying at least a bit under the radar in competitive circles, in an attempt at giving you information you might not have heard.
Chapter 1: Prankster Sableye, Or That Thing that was Never as Good as Spiritomb
Sableye. He's Dark/Ghost, giving him no weaknesses. This would normally make him a worthwhile asset, but because his base stats only come to a total of 380, he was a little worthless until now. However, with the ability Prankster, he can be quite the asset. Prankster makes all non-damaging moves to have an increased priority. (To be exact, their priority increases by 1.) This means he can set up the opponent with some status effects and stall until they die. Because he doesn't have weaknesses and has access to recover, it can make him a tough Poke. Here's an idea for his set:
Sableye w/ Lagging Tail
Careful Nature (Increases Sp. Defence, decreases Sp. Attk)
EVs: 252 HP, 120 Def, 136 Sp. Def (The reason Sp. Def gets more is because his Sp. Def is lower than Def.)
Recover (By breeding)
The reason for lagging tail is so you can trick it over to your opponent, so that even when you faint all of your other Pokes will still hit first. Lead with Confuse Ray, then hit them with Will-O-Wisp. If you come to a point where you are low on HP, use recover. Remember, you will move first with all of these moves, so you can recover before the opponent hits you.
Chapter 2: Moxie Heracross, Or Attack of the Killer...Dung Beetle?
Heracross is one of my all time favorite Pokémon, and now he is even better. Most of you are probably familiar with the ability moxie, which increases a Pokémon's attack after they cause an opponent's Pokémon to faint. Throw a Choice Scarf on him and he's a killing machine. With multiple STAB moves that are already 100 or more base power, Heracross becomes a fiend after one or two KO's. Here's the set I use:
Heracross w/ Choice Scarf
Adamant Nature (Increased attack, decreased Sp. Attack.)
EVs: 252 Attk, 252 Speed
Close Combat is your main attacking option, with Megahorn being a close second. Both are STAB moves w/ 120 power, but Close Combat is preferable because of its 100% accuracy, compared to Megahorn's 80%. That accuracy does come at the price of decreased defences on every hit. That's why we put Choice Scarf on there. Because you will probably be able to 1HKO anything that does not resist you, as long as your faster those defence drops shouldn't hurt. If you come up to a Pokémon that you think has an increased priority move, you should switch out. With all those defence drops you could be easily 1HKO'd yourself. Earthquake is here to fight common fire type threats, and Stone Edge is a last case scenario move if Heracross is your last Pokémon and you are facing a flying type.
Chapter 3: Magic Bounce Espeon, Or Take that, Ferrothorn!
Many people lead with a spiker Pokémon like Forretress or Ferrothorn. When you know they are going to hit you with Spikes or Stealth Rock you can switch into your Espeon, who has the new ability Magic Bounce, which will launch those traps right back at your opponent, so now they have entry hazzards instead of you. This also works for stat reducing moves and non-damaging status-ailment moves. Essentially this works for switching in and out, so I don't really have a required set, but here is what Smogon suggests:
"move 1: Reflect
move 2: Light Screen
move 3: Hidden Power Fighting / Hidden Power Ground / Hidden Power Fire
move 4: Psychic / Psycho Shock
item: Light Clay
ability: Magic Mirror
evs: 252 HP / 4 Def / 252 Spe" source
Chapter 4: Ditto, Or "Yeah I'm Serious."
Ditto was always cursed by being a few turns behind whatever it transformed into, due to the necessity to switch in and then transform. Ditto's new ability allows him to transform the second he switches in, effectively saving you a turn. Put a choice scarf on him and he will be faster than whatever he turns into, giving you quite the advantage. Switch in when you think the opponent will use a move that its own typing will resist or when you think the opponent has a move that would be super-effective against itself. There is no point in listing a moveset, because "Transform" is its only move and its EVs don't matter, because it matches the opponents stats. Just remember the choice scarf.