I figured since I have a friend who uses Cervantes, I could post some vids here of good crevy players and my thoughts about their gameplay. I'll probably do this for other characters as well, like Raph(steffan) and mitsu (tyler). I'll try to find some against NM too so you guys could see some anti-nightmare strats.
I'll post some stuff like GI mixup for characters, and other general stuff if I can think of any before the videos. For the GI mixup game for characters you should keep this in mind for what you use. The fast one must come out during the 20 frame window if they don't re-GI right away. For the slow option, you should restrict it to moves that are safe on block. Also keep in mind what moves will ring out or leave you in another good mixup.
Soul calibur IV 101:Numerical Conventions
7 8 9
4 5 6
1 2 3
translates to:
u/b u u/f
b n f
d/b d d/f
Or written out fully:
up-back, up, up-forward
back, neutral, forward
down-back, down, down-forward
Hint: Look at your numberpad on your computer keyboard.
Regardless of what side you play on (1p or 2p), 6 is always forward, and 4 is always back. Some more examples:
236 = QCF (quarter circle forward)
214 = QCB (quarter circle back)
63214 = HCB (half circle back)
Buttons
A: A horizontal attack.
B: A vertical attack.
K: A kick attack.
G: A guard.
Any: Any button can be pressed.
[any]: Hold down the button/direction.
_: Or. (B_A, meaning you can press B or A)
+: And. (B+G, meaning you have to press B and G together)
~/aB/bK/kB/bA/kA/aK: Any lowercase letter followed by a uppercase letter is a Slide input or input button immediately after. Input the buttons faster and in smooth conjunction. There are different timings for different slide inputs.
: : Just Frame input. (A:B - means B is input at the next frame)
General Notation:
NC: Natural Combo.
NCC: Natural Combo on Counter.
GC/GB: Guard Crush/Guard Break
BT: Back Turned.
FC: Fully crouched.
iFC: Instant Full Crouch.
WR: While Rising up (WS is also a generally accepted notation, I'll use them interchangeably)
iWR: Instant While Rising.
JF: Just Frame.
GI: Guard Impact.
KND: Knockdown.
TC: Tech Crouch.
TJ: Tech Jump.
AC: Air Control.
Guard Impacts
GI = Guard Impact (6G, 4G, 1G or 3G)
1G = Parry (mid/low)
4G = Parry (mid/high)
3G = Repel (mid/low)
6G = Repel (mid/high)
JI = Just Impact (otherwise known as perfect GI)
Stuns: When a stun occurs on a character yellow lightning covers the characters body. Stuns that are shakable always leave your character
standing after the stun ends. The stun can be broken out of with 5 non-diagonal (not 13579) directional inputs.
You should note that, for some stuns that can be broken out of doesn't necessarily mean that there is no combo afterwards. For example you cannot break out of Zasalamel's 6AB (stun) > BT B+K. Some moves are always guaranteed.
Tech(thanks to Kowtow, ojste, and Jaytech):
Tech is just getting up quicker when you get knocked down, time it as you hit the ground.
Wall tech is gone(from SCII), but to tech off the ground simply hit guard, and the direction you want to tech in. Guard alone will make you tech straight up, back will tech farther backwards, left and right will move you that way, and leave you in crouch for a very short period.
As far as when to use it, depends on the situation. A lot of characters have some "tech traps" which are situations where they can get in extra hits if you tech in the wrong direction. Most of this can be found in the specific soul arenas, but actually putting it to use in your defensive game will just take experience. Basically if you tech, and get hit, next time you get knocked down in that same way, don't tech or tech a different direction.
the most effective time to tech is when it will avoid damage that would of hit you had you stayed on the ground, but like kowtow said you have to be careful of tech traps as certain characters have specific moves, which can be used to hit you whilst you're teching.
you basically need to learn what your options are in different situations and decide for yourself and if its a 50/50 situation then you just gotta guess.
Schneider: Also, I'd like to add that in SCIII a "Just tech" was added to the game, which occurs when your juggled and are slammed back down to the ground. By pressing G as you hit the ground you can avoid follow up damage.
Also, because damage scaling can damper stun combos alot in SCIV, a tech trap will reset the damage scaling.
Thanks to
http://www.8wayrun.com/f6/newbie-silencer-t76/ for most of the info here.

I'm gonna have a separate post for each character I do to keep the info a bit more neat and organized. I'll try to find informative videos and such to help anyone interested in learning a character.
Edit:
August 03, 2009Added general notation and note about posting combo videos and such
Edit 2:
August 25, 2009Finished adding videos and character strategies for most played characters in scene.
Edit 3:
February 16, 2010Added some posts for Karel and Graeme.