Due to the inherently limited ductility at room temperature, cracks were almost inevitable in additively manufactured tungsten (W). In this study, we propose a novel W-5 wt.%Re-C ternary alloy with exceptional crack suppression fabricated using laser additive manufacturing. We analyze the advantageous effects of solutes on properties of the W matrix and investigate the influence of planar segregation of carbon (C) on active deformation through density functional theory calculations. In the experiment, carbon-based complexes (CBCs) featuring high-density stacking faults achieved through the planar segregation of C atoms were discovered. Infinite solid solution W2C-Re precipitates were also discovered. The formation of CBCs can alleviate stress concentration to facilitate coordinated deformation. This study investigates the influence of C addition on coordinated deformation behavior in W-based alloys, offering a novel approach for optimizing the performance of additive manufactured components based on W.