Eclipso is able to overshadow anyone who touches or comes into contact with the cursed Heart of Darkness gem, controlling the host's powers and influencing their behaviors and memories to Eclipso's own ends. He can then strengthen his host by either enhancing their normal capabilities or bestowing them with new powers. In his later appearances, Eclipso boasts even greater possession power than previously seen and after possessing Maxwell Lord, his abilities to possess and corrupt people were intensified. No longer needing people to physically touch the stone for him to affect them, he can remotely possess multiple hosts, providing he can corrupt them first. Furthermore, his influence can exacerbate the darker impulses of individuals who come under his sway and those whom he possesses undergo a visible transformation; gaining a more monstrous physical appearances. He can physically shift his main host's body into his true, more powerful, physical form.