Speed Modifier Tutorial
A speed modifier is a code that modifies the speed of an in-game character or object. In most cases, this is a 16 or 32-bit signed value in memory. When the character or object is stopped, the value is usually zero. Keep in mind that simpler systems such as the NES and GBC may use 8-bit values for the speed value
To hack this code, a slight deviation of the GLEE method may be used.
If the character is stands totally still on the ground, it's a reasonable assumption that the character's speed isn't changing. Start a an unknown value search (initial dump).
If the character jitters while standing or something, the Equal To searches mentioned here may need to be skipped. This makes it more difficult to narrow the results, but it's still possible.
Move around a bit, then stand still again. Search Equal To. Repeat this step a couple times to eliminate some junk results.
Now start moving. Without stopping, do a Greater Than search.
Once the character stops or diminishes in speed, do a Less Than search.
Repeat the steps above until the results list is narrowed considerably.
When ready to test some results, try setting the speed to something really low. If the character is going really slowly, a speed mod has been found!
Once the correct address is found, try different values until the desired level of speed is reached. A value set too high may launch the character careening through the level or it may even crash the game.
Once you have your code, it's a good idea to put an activator on it. Else, the character will always be moving at fast speeds. Some good choices for activators include a "moving/not moving" flag in memory, or even button activators if an alternative isn't found.
Tutorail made by: Unknown
Tutorail posted by: MF Tlaxcala