The red seaweed Asparagopsis armata, known for its ability to reduce methane emissions from enteric fermentation when incorporated as a ruminant feed additive, is a key target for aquaculture development. However, despite advancements in this field, there remains a critical gap in understanding the internal mechanisms governing reproduction in A. armata, as well as seaweeds in general. In this study, we examined metabolomic and transcriptomic changes throughout the induction of tetrasporogenesis in A. armata, utilising both targeted and untargeted approaches. These findings collectively offer a detailed overview of the processes underlying tetrasporogenesis in A. armata, facilitating further targeted investigations into the internal regulation of seaweed reproductive biology.