Ledian
Type: Bug/Flying
Abilities:
Swarm - Increases the power of Bug moves by 50% if Ledian is at 1/3 health.
Early Bird - Amount of sleep turns is cut in half
Dream World: Iron Fist - The power of punching moves is increased by 20%
Base Stats: 55 / 35 / 50 / 55 / 110 / 85
Movepool:

Type: Bug/Flying
Abilities:
Swarm - Increases the power of Bug moves by 50% if Ledian is at 1/3 health.
Early Bird - Amount of sleep turns is cut in half
Dream World: Iron Fist - The power of punching moves is increased by 20%
Base Stats: 55 / 35 / 50 / 55 / 110 / 85
Movepool:
Code:
Level-up:
Tackle
Supersonic
Comet Punch
Light Screen
Reflect
Safeguard
Mach Punch
[COLOR=Red]Baton Pass
[COLOR=Black][COLOR=Red]Silver Wind[/COLOR]
[COLOR=Red]Agility[/COLOR]
Swift
Double Edge
Bug Buzz
In-game NPC:
Double Edge
Air Cutter
Bug Bite
DynamicPunch
Endure
Headbutt
Ice Punch
Knock Off
Mega Punch
Mimic
Mud Slap
Ominous Wind
Rollout
Sleep Talk
Snore
String Shot
Substitute
Swagger
[COLOR=Red]Swords Dance[/COLOR]
Tail Wind
Thunderpunch
Uproar
[/COLOR][/COLOR]
TM:
Focus Punch
Toxic
Hidden Power
Sunny Day
Hyper Beam
Protect
Frustration
Return
Solarbeam
Dig
Brick Break
Double Team
Aerial Ace
Facade
Attract
Thief
Sing-a-round
Focus Blast
Fling
Acrobat
Giga Impact
Flash
Struggle Bug
U-turn
Rock Smash
Strength
Gen 5 Egg moves:
Psybeam
Bide
Screech
Encore
Focus Punch
Drain Punch
Gen 4 TM/Move Tutor Moves:
Giga Drain
[COLOR=Red]Roost[/COLOR]
Captivate
Natural Gift
Roll Out
Tail Wind
[set]
name: Realistic Baton Pass
ability: Early Bird
nature: Jolly
item: Focus Sash / Lum Berry
move 1: Encore
move 2: Agility
move 3: Swords Dance
move 4: Baton Pass
EVs: 152 HP / 104 SpD / 252 Spe
Does this look familiar? Probably not, unless you read every 4th Generation analysis on-site. This set has literally not changed in the transition to Black and White. Ledian needs maximum Speed and runs no attacking moves, so you are free to focus the rest of its EVs on its Special Bulk. Switch Ledian in on a Choice-locked Ground-type attack and start boosting, or switch into something slower and Encore its Grount-type attack. It's best to start with Agility while they switch, then Swords Dance, survive the oncoming hit with Focus Sash, hope they don't have a priority move, then Baton Pass the hell out of there.
In order for this set to work, there must be no Stealth Rock, Sandstorm, or hail on the field, and you must avoid enemy priority. Also, Mischievous Heart users totally ruin this set, so make sure they are out of the picture as well. All-in-all, this takes a ton of support and weather cancelling to work.
[set]
name: Screen Pass
ability: Early Bird
nature: Jolly
item: Light Clay / Lum Berry / Leftovers
move 1: Encore
move 3: Reflect
move 2: Light Screen / Agility / Swords Dance
move 4: Baton Pass
EVs: 136 HP / 120 Def / 252 Spe
Very similar strategy as above. Encore a setup or Ground-type move, Reflect on the switch to give Ledian more Physical Bulk. Light Screen is the recommended 3rd move, as it makes Ledian very Specially bulky, but you can take advantage of on-coming Physical attackers and set up Agility or Swords Dance. Once you have one screen and any other boosts, Baton Pass out of there.