All other constructs printed with 3, 5, and 7% GelMA were structurally sound and could be handled without damage (Supplementary Information, Figure ). The crosslinked constructs showcase the ability of the biomaterial inks to print complex models that are challenging, or impossible, to achieve with other protocols by direct extrusion 3D printing. The human ear shape, printed with the 3% GelMA ink, presented layers that are not fully supported by underlying layers, producing slight overhangs that lead to hollow spaces (Figure ). The nose, printed with the 5% GelMA ink, increased the complexity by presenting a completely hollow dome-like structure with soft angles (Figure ), while the hollow ghost figurine, printed with the 7% GelMA ink, presented more pronounced angles and overhanging features (Figure ). Overall, these results demonstrate that complex structures can be printed with GelMA-CBP inks and achieve outstanding printability and shape fidelity while maintaining the desired properties for bioprinting: low concentration of GelMA and additive, and printing at physiological temperature of 37 ºC. The ability to print complex constructs can be critical when using these materials for tissue engineering applications. Crosslinked GelMA-CBP materials can mimic the mechanical properties of tissue.