General properties

transparencyGives you the transparency of the object, for example use the 'change transparency by' brick and then controll the transparency with an 'if...is true then' brick.
brightnessGives you the brightness of the object, for example use the 'change brightness by' brick and then controll the brightness with an 'if...is true then' brick.
colourGives you the color of the object, for example use the 'set colour to' brick and then check the color with an 'if...is true then' brick.
look numberEvery object has a look number, look number 1 is the first look and look number 2 is the second and so on.
look nameEvery object also has a look name, everythime you insert a new look to an object you give it a look name.

Motion properties

position_xgives the current position_x of the object
position_ygives the current position_y of the object
sizecheck the current size of the object
directiongives the direction of the object, combine it with the 'Point in direction' brick and for example the if...then' brick
layerprovides the actual layer of the object
touches actor or objectgives a true when the object touches actors or an other object
touches edgegives a true when the object touches edge
touches fingergives a true when the object touches a finger
x velocity 
y velocity 
angular velocity