Sophisticated flexible strain sensors based on MXene/rubber with self-healing capabilities are poised to transform future deformable electronics by restoring impaired performance after repeated deformation. Despite their potential, integrating excellent self-healing properties with superior mechanical strength in a single system remains a significant challenge due to simplistic interface architectures with weak bonds and limited understanding of MXene/rubber interface dynamics. To address this, a novel metal coordination bonding scheme has been developed, synergizing with dynamic hydrogen bonding to enhance interface bonding strength, enabling both outstanding mechanical and self-healing properties. Using in situ synchrotron radiation techniques, a multiscale investigation of MXene/rubber interface dynamics provides valuable insights, linking bonding strength to mechanical performance. These findings not only deepen our understanding of interface evolution in deformable electrodes but also offer a promising path for designing advanced self-healable strain sensors with superior mechanical properties.