Looking after your alien involves adding slime food, exposure to the correct amount of daylight / darkness and letting the aliens cocoon dissolve over a fourteen-day period. The final size of the alien is 8 times the original birth size. Mistreat your alien and its heart will change colour; prompting you to give it the care it deserves (poor little alien). As your alien grows, its electronic heart will start to beat until it’s finally removed from its test tube upon complete growth. Once fully grown the aliens have the power to glow in the dark and with six to collect your night time will never be the same again!