 His virtual invulnerability offers no protection from mind control or magic, nor can it fully withstand the force of an atomic explosion or the force of opponents with greater strength and durability such as Doomsday.His superhuman strength is inferior to beings such as Doomsday and his superhuman speed is inferior to Speedsters such as the Flash.Jax-Ur's intelligence does give him the advantage of utilizing his strength and speed to optimal performance.