Shows like Voltron: Legendary Defender

After Keith, Lance, Pidge, Hunk, and Shiro are sent into space in a blue lion, they find two "alteans" by the names of Allura and Coran who have been frozen in crypto-pods for ten thousand years. They then discover that they must each pilot one of the robotic lions of Voltron, and defend the universe from an alien species called the "galra", and their evil emperor "Zarkon."