High-energy and high-intensity lasers are essential for pushing the boundaries of science. Their development has allowed leaps forward in basic research areas including laser- plasma interaction, high-energy density science, metrology, biology and medical technol- ogy. The HiBEF user consortium contributes and operates two high-peak-power optical lasers at the HED instrument of the European XFEL facility. These lasers will be used to generate transient extreme states of density and temperature to be probed by the X-Ray beam. This article introduces the ReLaX laser, a short-pulse high-intensity Ti:Sa laser sys- tem, and discusses its characteristics as available for user experiments. It will also present first experimental commissioning results validating its successful integration into the EuXFEL infrastructure and viability as a relativistic-intensity laser driver.