Easiest way to do this is by waiting for the last train of balls on a level, make sure you have plenty of room. Then wittle them down to two colours then alternate 2 by 2 by 2 etc into a big row until you have 18. Hit the middle and they will all come together in fours, beautiful!
- Play well so the last train of balls is at the start of the run
- Remove all balls except two (of different colors)
- Fire so that you have a long line of 18 in 2 by 2 formation
*Ensure you do not make a 3
- Hit the middle