The Beasts From Ganymede

When they decided to leave their dwarf planet, these Gamymades had already conquered Jupiter, Saturn, Neptune, Uranus and planned to seize Venus and Mars; they are huge, horrifying beasts with swarthy, hard skin and bellicose eyes so fiery... they set soil ablaze with their hard breath, making smoke rise higher than clouds: be warned, they'll invade Earth and enslave us and destroy all we built over the ages!