Whilst regularly the subject of mockery, Billy Dawkins power as a Chameleon is actually quite impressive. He is able to change the colour of himself and things around him to blend invisibly into the background.
Had he not been kidnapped and subjected to brain damaging Wiping and Memory Replacement by Owen and Tereska, he would have been able to use his power in many ways including spying and self protection.
CHILDHOOD AND FAMILY
Billy came from a very loving and supportive background, though his parents never really encouraged him to do anything with his gift beyond having fun. His mother, an Empath, firmly believes that children should be children and carefully monitored his moods to ensure at all times he was as happy as possible.
When he met Ashya and Amy he discovered his powers could be used for more, though never felt confident in doing so, both out of shyness and due to his parents political leanings. When Alex and his friends began mocking him for his gift, he became defensive and resentful of those with more active powers.