You can have 8 directions simulate control left, right, up and down..
You only have to create the conditions for it..
for example:
Give the chap instance variable movement (number)
every random(1,5) seconds
for each chap
- set chap variable movement : choose(1,2,3,4,5,6,7,8,9)
for each chap
- chap variable movement = 9
-- chap 8 direction simulate control up
-- chap 8 direction simulate control right
- chap variable movement = 5
-- chap 8 direction simulate control left
I used 1 to 9 so you can easily compare them to the numbers on the numpad..