The European XFEL is currently the world's most powerful free-electron laser and has, over the past decade, significantly advanced the ability to resolve the structure of matter with X-rays. Growing interest in ultra-hard X-rays is now driving efforts to extend the facility's routine operating range into the sub-ångström regime, where photon energies of 25 keV and above are required. Access to such high-energy X-rays enables larger penetration depths and the investigation of materials under highly absorbing or extreme conditions. Achieving these capabilities is essential for the continued development of the European XFEL. The facility's unique strengths, its high-energy linac and long, variable-gap undulator systems, provide a solid foundation for generating intense X-rays at 25 keV and or pushing the performance frontier toward 30 keV. However, the FEL output critically depends on the quality of the electron bunches. Producing low-emittance beams through advanced spatial and temporal laser pulse shaping, together with accurate modelling of the underlying beam physics, is therefore a key prerequisite for fully exploiting the XFEL's potential. Dedicated numerical and experimental studies of the accelerator and FEL systems are needed to enable scientific opportunities at photon energies.