Dragon Warrior I & II

Years after its release, its gameplay mechanics have been described as simplistic and spartan. The player controls a young hero who sets out to defeat a being known as the Dragonlord. The player starts with a menu to begin a new quest, continue a previous quest, or change the speed in which messages appear on the screen. In the Japanese version, continuing a quest requires a password .

In the North American Nintendo Entertainment System (NES) English version, the quest is saved onto the game cartridge's battery-backup (called an "Adventure Log" in the "Imperial Scrolls of Honor"), with options to delete or duplicate a saved quest. In a new quest, the player may give the hero any name; the game analyzes the name entered to determine the initial ability scores and their statistical growth over the course of the game. Dragon Warrior presents players with a clear objective from the start and uses a series of smaller scenarios to increase the hero's strength in order to achieve the objective. The game begins in King Lorik's chamber in Tantegel Castle, where the hero receives information about the Dragonlord, whom he must defeat, and the stolen Balls of Light, which he must retrieve.

After receiving some items and gold, the hero sets out on his quest. Much of Dragon Warrior is spent talking to townspeople and gathering information from them that leads to additional places, events, and secrets. Towns contain shops that sell improved weapons and armor; general stores where the player may buy other goods; inns that allow the hero to recover his health and magic, and shops that offer keys for purchase. The player may sell items at half price to shops that provide weapons, armor, or general goods.

The hero's status window is shown whenever he stops moving, displaying his current experience level (LV) and the number of hit points (HP), magic points (MP), gold (G), and experience points (E). To safely progress to the next areas in the game, the player needs to accumulate experience points and gold by defeating enemies outside of towns – in the overworld and in dungeons. Apart from the Dragonlord's castle and locked doors, there are no physical restrictions on where players can roam. Instead, monsters increase in difficulty as players venture further from Tantegel castle.

As the hero's level increases, the player can explore further afield with less risk. Enemies appear in random encounters and the hero fights one opponent at a time. The encounter rate is lowest on fields and increases in forests and hills. Battles are turn-based and fought from a first-person perspective while the hero remains off-screen.

In combat, players must defeat the enemy by reducing its HP to zero. During combat, players have four commands: "fight", "run", "spell", and "item". The "fight" command causes the hero to attack the enemy with a weapon, or with his bare fists if no weapon is available, in an attempt to inflict damage. With the "run" command, the hero attempts to escape from a battle, which is recommended if his HP is low.

The "spell" command casts magic that can, for example, heal the hero or damage the enemy. The "item" command uses herbs that replenish the hero's HP. During combat, the hero loses HP when he takes damage, and the display turns red when his HP is low. If his HP falls to zero, he dies and is taken back to King Lorik to be resurrected, and loses half his gold "as punishment".

If the hero succeeds in defeating an enemy, he gains experience points and gold; if he gains enough experience points, his experience level increases, giving him greater strength, agility, speed, and the ability to use magic spells. Every time a spell is used, the hero's MP decreases at a different cost per spell. Both HP and MP can be restored by resting at an inn, and a non-player character can replenish the hero's MP in Tantegel Castle. As the hero earns more gold, better weapons, armor, and items can be purchased.

The player can conservatively manage the limited inventory space. Exploring the dark caves requires a torch or the "RADIANT" spell to display a temporary field of vision. In the English version, the player can return to King Lorik at any time to save the quest. The control pad moves the hero and the menu cursor.

Other buttons confirm and cancel commands. The English version has menu commands to talk to people, check their status, search beneath their feet, use items, take treasure chests, open doors, and use stairs. In some remakes, certain commands are assigned to buttons, navigating stairs is automatic, and the hero's speed is higher.