The King of Dragons (ザ・キングオブドラゴンズ) is a 1991 side-scrolling hack and slash arcade game by Capcom that allows players to choose from five characters (Elf, Wizard, Fighter, Cleric, and Dwarf) in order to travel through the kingdom of Malus and defeat the monsters that have taken over, as well as their leader, the red dragon Gildiss. The setting is very similar to that of Dungeons and Dragons and other medieval fantasy worlds, with familiar monsters such as Orcs, Gnolls, Harpies, Wyverns, Cyclopes, and Minotaurs. The game has 16 levels, though many are quite short.
Much like Capcom's Knights of the Round, King of Dragons features an RPG-like level advancement system. Points scored for killing monsters and picking up gold count towards experience, and the character gains levels at regular intervals. With each level, the character's health bar increases, other attributes such as range improve, and the character also becomes invulnerable for a few seconds. Along the way, different weapon and armor upgrades for each character may also be picked up.
King of Dragons features a simple control system that consists of a single attack button, and a jump button. By pressing both buttons, the character unleashes a magical attack that strikes all enemies in screen (its strength varies according to the character used) at the expense of losing energy. The fighter, cleric and dwarf can also use their shield to block certain attacks by tilting the joystick back right before the impact.
The game was ported to the Super NES in 1994. This port reduces the number of simultaneous players down to 2. The sprites' size were also reduced moderately. It is also possible to assign the magic attack and shield defense to different buttons.
The arcade version is part of Capcom Classics Collection Vol. 2, which was released for the PS2 & Xbox in November 2006. This was also in Capcom Classics Collection: Reloaded for the PlayStation Portable.
Source: Wikipedia, "King of dragons", available under the CC-BY-SA License.