A well-known example of a randomised mechanism in videogames is the lootbox, a virtual container of in-game items that distributes rewards to players that open it via a randomised process. Due to the importance of empirical research for the legal analysis, this chapter dives deep into the state of the art regarding the risks and harms associated with lootbox engagement for children and adults. Further, it explains in-depth how in-game economies work and why it is important to not only consider the lootbox mechanism itself, but also look at its function and importance for the gameplay experience.