We aim to design and build reproducible phantoms with anatomy-mimicking resolution and image contrast. We mix solutions of paramagnetic ions in agar gel to target specific relaxation parameters. Chambers for different tissue types are 3D printed and filled with the agar gels. Microfiber cloths are added to create additional high-resolution structure. We validate the ability to reproduce target relaxation values through spin-echo imaging and quantitative mapping, and present two 3D printed phantom designs.