We have built and implemented a set of metaphors for breathing games by involving children and experts. These games are made to facilitate prevention of asthma exacerbation via regular monitoring of children with asthma through spirometry at home. To instruct and trigger children to execute the (unsupervised) spirometry correctly, we have created interactive metaphors that respond in real-time to the child's inhalation and exhalation. Eleven metaphors have been developed in detail. Three metaphors have been fully implemented based on current guidelines for spirometry and were tested with 30 asthmatic children. Each includes multi-target incentives, responding to three different target values (inhalation, peak expiration, and complete exhalation). We postulate that the metaphors should use separate goals for these targets, have independent responses, and allow to also go beyond expected values for each of these targets. From the selected metaphors, most children preferred a dragon breathing fire and a soccer player kicking a ball into a goal as a metaphor; least liked were blowing seeds of a dandelion and applying lotion to a dog to grow its hair. Based on this project we discuss the potential and benefits of a suite-of-games approach: multiple games that each can be selected and adapted depending on personal capabilities and interests. CCS CONCEPTS• Human-centered computing → Empirical studies in ubiquitous and mobile computing; User studies.