Let me clear a few things before I start

1. This is my first post ever, so it's not gonna look very professional I guess

2. English is not my primary language, but I will try to make myself understandable.
3. I designed this build by myself and I did not copy it from another player. I do not know if there are any similar builds or builds that serve the same purpose.
4. This build is not made for dealing damage, if your looking for some major
dmg build, this isn't the place for you

4. This build requires 2 characters to fully function, I will explain why.
Ok let's start!
Profession: E/Me
Name: Constant Knockdown
Type: PvE (PvP is possible, will add build for PvP)
Category: Interrupt
Attributes:
Air Magic: 12+3
Energy Storage: 12+3+1
6 attribute points at your disposal
Skills:
[card]Lightning Strike[/card][card]Whirlwind[/card][card]Glyph of Elemental Power[/card][card]Thunderclap[/card][card]Glyph of Lesser Energy[/card][card]Arcane Mimicry[/card][card]Aura of Restoration[/card][card]Resurrection Signet[/card]
[skill=big]Thunderclap[/skill]
Second party member:
Profession: E/N or N/E (doesn't really matter)
Crucial Attributes:
Blood magic 12 (or higher)
Crucial Skills:
[card]Blood Ritual[/card]
[skill=big]Ether Prism[/skill]
The other slots are at your disposal, just make sure your hero/friend has the above skills.
Things you need:
Shocking Feathered Flatbow (of Fortitude, can be something else) >> shockbow.JPG
with the +5 energy inscription. (You can get this bow, without the Shocking bow string and without the bowgrip of Fortitude at Weaponsmith Ruricu in Crystal Overlook, see http://gw.gamewikis.org/wiki/Weaponsmiths_%28Nightfall%29#Crystal_Overlook_weap onsmith_Ruricu for more information.
5 Radiant Insignias (energy bonus on every armor part)
2 Runes of Attunement
1 Rune of Superior Air Magic
1 Rune of Superior Energy Storage
1 Rune of (Min,Maj,Sup) Vigor to regain some hp
Summary:
Ok as I stated above, this build is not made for dealing dmg. The purpose of this build is to constantly knockdown a foe and thus support your team by making foes (or preferrably mobs) incapable of doing anything (except skills that activate instantly & such)
How does it work?
Thunderclap knocks down a foe, everytime they get struck by lightning dmg. So with a shocking bowstring on your bow, you can knock down a foe consecutively without having to use air magic spells that eventually drain to much energy, since Thunderclap already drains 6/7 energy when you strike a foe. (with 15 Air magic)
Why not use a melee weapon or another kind of bow?
Melee weapons and staves have an attack intervall of 1.33 sec or 1.75 sec, which is less than the time a foe needs to get up after being knocked down (approximately 2.0 sec) Hitting a foe with a (Flat)bow will be more effective and efficient because the flatbow has an attack intervall of 2.0 sec, knocking foes down each time they get up.
All succesfull hits with TC will cause energy drainage, and foes can't be knocked down whilst they're getting up, thus making some melee attacks a complete waste of energy once you hit them while they're still down.
(See video, link at bottom of post)
Energy Management
To reduce the energy drained by TC, I use Glyph of Elemental power, which raises your elemental attributes by 2. Giving you lvl17 in Air Magic. With lvl17 Air Magic, TC will drain 6 energy iso 7.
So now your knocking down foes and getting low on energy. Here's where your hero/ally becomes important:
- Use Glyph of Lesser energy to reduce the energy cost of Arcane Mimicry and Ether prism.
- Cast Arcane Mimicry on your ally.
- AM now becomes Ether Prism. Cast Ether Prism at approximately 40 energy to fill
your energy gauge back up.
Now you can start the process all over again.
Have your ally use Blood Ritual all the time to regen energy.
* Whirlwind can be used to knock down attacking foes when you aggro to much.
* Lightning Strike can be used if you need to knock down a foe quickly because the bow can be too slow at some moments.
PvP build
This is the PvP version of the build, although it's not very effective; monks can easily remove TC because it's a hex. And the energy management sucks.
It's very funny though and really bugs players
Profession: E/P (or any other profession that gives energy regen/management)
Attributes:
Air Magic: 12+3+1
Energy Storage: 11+1
Motivation: 6
Skills:
[card]Lightning Strike[/card][card]Whirlwind[/card][card]Lightning Orb[/card][card]Thunderclap[/card][card]Song of Power[/card][card]Air Attunement[/card][card]Aura of Restoration[/card][card]Resurrection Signet[/card]
(Have also tried with Zealous Renewal (D) but that would only return 10 energy since you will only hit 10 times in 20 sec.)
[card]Zealous Renewal[/card]
This also requires the shocking flatbow >> shockbow.JPG
*Note, this PvP build is very unstable, not really very effective, but it's a good laugh when you succeed. (Don't comment to much about this)
Hints and tips are always welcome!
You are free to change this build with your own favorite skills and such.
Feel free to post it anywhere, credits go to me though

Grtz, Skylancer
* Update (Credits go to Francis Crawford)
You can use a weapon(set) with "Seize the day!" Inscriptions before you cast Ether Prism to raise your max energy by 30 points at least.
- I have recorded a video to enlighten things a little bit, although the quality isn't very good.
http://http://www.youtube.com/watch?v=-jwfetwmTWw
* Update
- Added skill icons with mouseover
Don't know how it works? Check: http://www.guildwarsguru.com/forum/showthread.php?t=10067189&referrerid=&highlight=sk ill+card
- Some minor adjustments