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FD Brake
Tap Faultless Defense while Running
FD Brake is a technique that avoids the Run Skid animation by canceling one's run into Faultless Defense.
This lets the user block out of a run sooner than they normally would by bypassing the run skid animation. Additionally, FD Brake lets the user manipulate their forwards momentum. To perform an FD Brake, briefly tap the Fautlless Defense input while running.
Both standing and crouching FD Brake preserve some of the sliding momentum, but this can be negated by briefly transitioning to a backwards walk after the FD input.
FD Slide
Walk Forwards after FD Brake with Sliding Momentum
With a precise input, one can transition directly from the FD input to a forwards walk input. This will add the sliding momentum to the user's forwards walking speed.
SB Brake
Tap Slashback while Running
Slashback brake is similar to FD Brake for modifying the user's momentum, but without the blocking aspect.
SB Brake will completely negate forwards momentum, whether performed standing or crouching. Furthermore, all of the rules from Slashback apply. This means that the user will not be able to guard for a period of time after the SB brake.
FD Jump
Use Faultless Defense During Prejump
FD Jump is a defensive technique used to avoid getting hit while jumping.
This technique will cause the user's character to immediately enter their air FD state as soon as the prejump animation ends. This has the obvious benefit of allowing the user to block grounded attacks immediately after jumping, but also has character specific benefits based on their air FD Hurtbox. Some characters, such as 
Kliff and 
Venom, have especially small air FD hurtboxes. This can cause the opponent's attacks to miss where they would normally hit the standard air hurtbox.
A successful FD Jump will not show the jumping smoke cloud effect, nor play the jumping sound effect.
Venom's hurtbox on the first frame after prejump
Venom's air FD hurtbox on the first frame after prejump
Instant Air Dash
956 (forwards) or 754 (backwards)
Instant Air Dash, IAD, is a method of performing an air dash, either forwards or backwards, as quickly as possible from a grounded state.
This technique works because the initial, diagonal jump input counts as the first forwards or backwards input of the air dash. IAD is useful in combos, neutral, and sometimes defense depending on the character.
Common Option Selects
Button Priority
In +R, button inputs have a priority system. If two buttons are pressed at the same time, then the move whose input uses the higher priority button will come out.
The priority for buttons is, from highest to lowest, D > P > K > S > H.
Throw OS
6+H+a Higher Priority Button
Throw OS is an option select A technique where one command (or series of commands) will perform a different action depending on the circumstances, thereby allowing one action to be able to handle two distinct situations. that allows the user to default to a normal other than 5H or 6H when the opponent is potentially not throwable.
+R Throws consist of a distance check, a check to see if the opponent is in a throwable state, and a check to see if the opponent matches the thrower's airborne/grounded state. If the conditions for a throw are not met, then the thrower will instead perform whatever attack matches the buttons they input. This would normally result in the thrower's character performing 5H or 6H. 5H will occur if the direction + H input does not correspond to a valid 6H input—in the case the character does not have a 6H move, or the throw was input with 4.
Throw OS allows the user to have their throw-misses default to faster, safer normals. OSing a throw is as simple as inputting another, higher priority button during a throw input. Which normal is used will depend on the character, but common examples include 6P and 6K—6PH or 6KH. In these examples, the thrower will perform 6P or 6K if the opponent cannot be thrown at that moment.
If all conditions for ground throw are met, then ground throw will occur
A throw input of 6H will give 6H if the throw conditions aren't met
A throw input of 6KH will give 5K if the throw conditions aren't met
Throw OSes also apply to air throws, and are input in the same manner. Air throws are most commonly OSed using a character's j.P because most are fast, and are generally safe to whiff due to their short duration.
If all conditions for air throw are met, then air throw will occur
An air throw input of j.6H will give j.H if the throw conditions aren't met
An air throw input of j.6PH will give j.P if the throw conditions aren't met
Throw Burst OS
4 or 6+H+D
Because throw has higher input priority than Burst, the user will perform a throw with a 6HD input if all of the conditions for a throw are met, and will otherwise perform Burst.
Tech FD
Hold 1 button for FD, a backwards direction, and rapidly press other buttons for FD
Tech FD is an option select A technique where one command (or series of commands) will perform a different action depending on the circumstances, thereby allowing one action to be able to handle two distinct situations. that mitigates the risk associated with teching.
Normally, it is possible for the defending player to press buttons either too slowly or too quickly when attempting to air tech. This would result in them either missing tech opportunities, or accidentally attacking after teching.
By option selecting the air tech input with Faultless Defense, Tech FD protects against over-mashing. Instead of accidentally performing a normal attack if you press buttons too many times, you will instead perform Faultless Defense, which is notably lower risk. Furthermore, Faultless Defense can be an inherently favorable option to perform after teching, because it allows you to block the opponent's attempts at using air-unblockable attacks as resets.
6FRC6
6 > FRC > 6
6FRC6 is a technique which allows a player to perform a dash the first frame a character becomes actionable after performing a Force Roman Cancel A Roman Cancel unique to the Guilty Gear XX series that costs 25 meter in exchange for only being able to be executed during a specific period of a special move. Usually abbreviated to FRC. Using 6FRC6 to buffer a dash lets players move quicker than they would normally be able to by manually inputting a dash after an RC or FRC, and is essential for certain combos, and can make certain combos easier than they would be otherwise
Jump Install
Impossible Dust
FD Cancel
Tech Buttons
Slashback Input Tricks
