Research and experience have already shown that games can be efficiently applied in a huge set of learning contexts, and that games can engage learners in ways other tools and approaches cannot. Hospitalized children have to cope with many disadvantages that can lead to physical, psychological, and technological impairments. New technologies and particularly games in mobile devices could be very important because they can prevent children from feeling as if they were living isolated and alone. In this paper we describe research carried out into a multi-player (collaborative) game designed according to the principles of a) Digital Game-Based Learning (DGBL) and b) Computer-Supported Collaborative Learning (CSCL). However, we have carried out a pilot study to evaluate the user experience (UX), including the social competences and emotional states, in multi-user virtual environments (MUVEs). Our main hypothesis states that tools based on DGBL + CSCL provide better support not only to the learning process of ill hospitalized children but the development of significant skills like communication, collaboration and team work, and as result, user experience is improved.