Watching Gymkata repeatedly has been a very important part of my life ever since I was in college. I have gone through the trouble to go to amazon.com and buy the new Gymkata DVD recently but before the DVD existed I owned the VHS which was one of my most prized possessions.
http://www.youtube.com/watch?v=9Mkl9rtttog
I realized that what Shadowrun needs is Gymkata. In any good film you always need some kind of superior martial art that lets the hero prevail. It might be better because it's older, or because it's newer, depending on if the martial arts films you watch come from Hong Kong or from Hollywood. It might even be better because it means you're drunker, which is always fun.
However, when we're talking Gymkata, we need something truly awesome and totally indomitable. Just look at the pommel horse fight scene: http://www.youtube.com/watch?v=-gTkUcXGF_Q . Even though Kurt Tomas was basically facing a +120 TN penalty due to Enemies In Melee the fact he could use Gymkata to its full effect by the pommel horse being there in the town filled with criminally insane people meant that he punk'd them all. Basically, we need something so awesome that should it appear in a campaign not centered around Gymkata it should cause that campaign to EXPLODE.
Now, SR4 is far too complicated and convoluted for my puny mind to understand. I can only think in the straightforward, simple, and concise terms of SR3.
So, here we go:
1.) A character may not have a Gymkata skill level higher than the average of his Athletics (Gymnastics) and Unarmed Combat skill. Gymkata is linked to Quickness and must be purchased using chargen points or karma seperately from those two skills. Furthermore, in order to learn Gymkata a character needs 2 trainers instead of just 1 like for most other skills, and furthermore one of the trainers must be Asian and speak English poorly and the other must be a heavily muscled African American who is proficient in horseback riding, unarmed combat, and staff fighting. This extra cost justifies it being super powerful and campaign-wrecking.
2.) A character may always apply a number of dice equal to his Gymkata skill level to any dodge tests as though these dice were combat pool dice. These dice may also stack with the dice provided by using Athletics to be harder to hit, to reduce damage from falling, to jump farther, or in any other situation the GM feels is appropriate.
3.) Instead of attacking, a character using Gymkata may perform confusing combat gymnastics flips as a Complex Action. If the character's next action is either a Gymkata attack or Full Defense, the opponent must roll the combat skill he is using in an opposed test against the Gymkata exponent's Gymkata skill level. For every 2 net successes the Gymkata exponent earns, his opponent's TN for melee against the Gymkata exponent is raised by +1. If the opponent is NOT using Gymkata, but is rather using Unarmed Combat or a lesser martial art, his TN for the opposed test is raised by 1.
4.) If a character uses Gymkata within a 5 meter radius of a pommel horse, high bar, balance beam, or any other gymnastics fixture, any and all TN modifiers that would otherwise apply due to Enemies In Melee and Reach to melee involving the Gymkata exponent are completely negated provided that the character chooses to fight or defend using his Gymkata skill.
5.) The Gymkata skill may be used in conjunction with a long staff. This is because Kurt Thomas uses a staff a few times in Gymkata and let's face it, the 2 point Reach is just so cheesy in the first place that as long as we're making the ultimate campaign exploding skill we should have a chance to use this tool in our quest for brokenness.
6.) A number of dice equal to the Gymkata skill level may be added to Perception tests for the purpose of noticing and reacting to ambushes, and incoming sniper arrows, without being totally surprised and not being able to react properly. This is because during your training the aforementioned Asian trainer tells you "heaa the onry sound of axe...cutting air." That's why you specifically need the Asian trainer for the Gymkata, see?