This regenerative transitions design paper critically reflects on Becoming Regenerative (B-Regen), an ongoing, three-year UKRI-funded research project tracing how regenerative design practices emerge, evolve, and attempt to gain momentum within entrenched and often degenerative economic, policy, and infrastructural systems. Our argument is that ventures with regenerative intent cannot realise fully regenerative outcomes within infrastructures and systems designed around extractive logics; therefore systemic change and transitional infrastructure is needed to collectively reimagine and redesign the conditions of possibility. We seek to illustrate what a transition-oriented regenerative ecosystem design project looks like in practice: one that moves beyond isolated innovation and toward relational, collective, and adaptive eco-social transformation through design-led speculative workshops.