The switched sequence of the concepts "Simulation" and "Synthesis" in the title of the conference emphasizes some changes within the Alife community. The Alife XII submissions consist of a significantly higher fraction of wet Alife papers than at any earlier Alife conference. The submissions are also congruent with a clearer view in the broader scientific community on how we might create life either from scratch or through top-down design.Significant progress has also been made for life-like robotics systems—for example, through the development of polymorphic robots, where simple self-assembly, self-replication, and complex collective behavior now have been obtained.In general, these proceedings demonstrate more integration between wet, hard, soft, and mixed living systems both within the Alife community and across the broader scientific and technological landscapes. This is in part captured by the definition of emerging living technology which comprises all technological applications of living and life-like processes at all levels.As the Alife community inches closer to an understanding of life as a physical process by constructing living processes, it is also increasingly assessing the technological implications of the ability to engineer systems, whose power is based on the core features of life: robustness, adaptation, self-repair, self-assembly, and self-replication, centralized and distributed intelligence, and evolution.This is an open access title from MIT Press: https://mitpress.mit.edu/books/artificial-life-xii