7. Lion-O (Thundercats)
Lion-O is the leader and hereditary "Lord of the ThunderCats". He wields the Sword of Omens, a powerful weapon that is often both his and the Thundercats' last resort in their fight against evil. As the only living individual capable of wielding such power, he could be considered Third Earth's last hope in the event of an all-out attack by the likes of Mumm-Ra. For this reason, Lion-O would make a fantastic Blue Lantern. Giving him the blue power ring to go with his sword would make him an exceptionally powerful warrior and enable him to defend Third Earth from evil much more emphatically.