Overview

In this hack and slash game, the central goal is to slay the many demons summoned by Diablo, the Lord of Terror, in a sixteen-level "labyrinth" underneath the small town of Tristram, and ultimately confront Diablo himself. Diablo contains replayability because of its randomly generated levels, which are in turn randomly populated with monsters that drop random items imbued with random magical properties.

Diablo in many ways resembles roguelike games, the main differences being more realistic graphics (utilizing DirectX) and the fact the game is in real time, rather than turn based.

Its popular sequel and its subsequent expansion pack extend the gameplay through additions such as new character classes, monsters, items, quests, areas, and plot. The latest installment, the expansion pack for Diablo II, Diablo II: Lord of Destruction has a huge online gaming community, complete with a primitive gameworld economy due to the rarity of most of the popular items.

Classes

The three character classes of Diablo are the warrior, rogue, and sorcerer. Each character, following typical role-playing conventions, has his or her own particular traits. The warrior possesses physical strength, the rogue is very agile, and the sorcerer is oriented towards magic. However, unlike modern class-based games, character's abilities are not unique; a warrior can use spells and a sorcerer can use a bow.

• Warrior: The warrior is a powerful melee fighter, master of weapons of war and capable of enduring more damage than any of the other classes. Seeking fortune and glory, warriors come to Tristram every day to challenge the dark unknown in the subterranean labyrinth. They are not necessarily of any particular clan or group and range from barbarians from the northern highlands to noble paladins. Warriors are able to repair their equipment at the cost of diminishing maximum durability. The amount of maximum durability lost with use decreases as character level increases. Given this lost durability, most players opt instead to pay for non-destructive repairs in town for equipment they will be using in the long-term.

• Rogue: The Sisters of the Sightless Eye are the best archers in the world of Sanctuary and the Rogue therefore is master of killing enemies from a distance. They are more intelligent than warriors and thus able to make good use of magic in their battles, although not nearly as well as sorcerers. Willing to test their skills against the evil in the labyrinth, where untold riches are rumored to be stashed, Rogues have come from the Far East to Tristram. Rogues have the ability to spot doors, chests and sarcophagi that have traps are able to disarm them. The chance to successfully disarm a trap increases with the character's dexterity attribute.

• Sorcerer: A powerful master of the arcane arts, the sorcerer is the hero that is able to achieve the greatest heights of magic, so that he may never use weapons - he can kill his enemies solely with magic, whether it would be balls and walls of fire or powerful bolts of lightning. Eager to gather knowledge about demons and see them slain, Sorcerer Acolytes of the Vizjerei mage clan have come to Tristram - seeking to discover long lost tomes of magic knowledge under the cathedral. The sorcerer is able to recharge magic staves at the cost of the maximum number of charges. The amount of maximum charges lost with use decreases as character level increases. As per the warrior class's skill, this is less-used in late-game and with equipment used in the long-term.

Character Attributes

The four numerical character attributes in Diablo affect the characters' combat statistics which in turn determine how powerful the character is. With each level up, five points may be distributed among the "Base" attributes to permanently increase them at the player's choice. They may also be modified by elixirs and magical shrines encountered in the game. Various magical items acquired in game increase the effective character attributes "Now" (while these items are being used).

• Strength affects the amount of damage the character may deal in melee combat. Advanced armor and weapons have minimum Strength requirements.
• Magic affects the amount of mana the character has (see Character Statistics). Magic affects the chance of a spell striking its target. Also, many spells are affected in some way (such as damage dealt or duration) by the Magic attribute. Spellbooks, staves, and many scrolls have minimum Magic requirements.
• Dexterity affects the chance of hitting enemies in combat and the chance of being hit by enemies. It also increases the amount of damage dealt by ranged attacks (for the Rogue only). Advanced bows have minimum Dexterity requirements.
• Vitality affects the Life statistic of the character (see Character Statistics). It also determines how much damage a monster needs to deal in order to kill the character.

Character Statistics

• Life represents how much damage the character can take before dying, also informally called "hit points". The amount of Life remaining is constantly displayed as a red orb on the left.
• Mana represents the character's spiritual life force. Casting spells requires mana. Therefore the more mana is available, the more spells can be cast. The amount of Mana remaining is constantly displayed as a blue orb on the right.
• Chance to Hit represents the likelihood that physical attacks will inflict damage on their targets. The caveat is that players must carefully control ranged attacks to actually enter the game tiles that their targets occupy; failing this, there is zero chance to hit.
• Armor Class represents the amount and quality of armor worn as a whole, modeling this as a reduction in chance of being hit. The body location, type of armor (fabric, chain, plate), and type of attack (bow, sword, etc.) are not considered by the game in combat. Armor does not protect a character against magical attacks.
• Damage represents the reduction in Life a physical attack will cause if it hits.
• Resist Fire, Resist Lightning, and Resist Magic represent the character's ability to resist damage from the respective categories of magical attacks. "Magic" attacks are all those that are not fire or lightning, which include magical acid. These statistics can only be non-zero as a result of the use of magical items, as characters can never innately possess resistance. None of the resistances can exceed 75% under any conditions for any character, though some creatures in the Labyrinth have immunities to Fire, Lightning, or Magic.

Monsters

The monsters of Diablo are undead monstrosities, vicious creatures of the night, and demons spawned from Hell. As the player progresses, he passes through four distinct areas: the church, the catacombs, the caves, and Hell, which starts to seep into the mortal plane due to Diablo's presence. Each of the sixteen levels contains monsters that are tougher and stronger than ones from the level before it. When the player kills a monster, the monster may randomly drop an item or gold.

In the world of Diablo, monsters are divided according to their masters.

The followers of Mephisto, the Lord of Hatred, are the undead (skeletons and zombies), demonically corrupted creatures whose unshapely forms and twisted limbs leave them in eternal agony and rage (overlords), and lava demons spawned by the spilling of Mephisto's blood in Hell.

The followers of Baal, the Lord of Destruction, are creatures that seek the undoing of the physical Universe and the manifestation of chaos. Some of them include the Fallen Ones, Goat Men and Poison Spitters.

The minions of Diablo, the Lord of Terror, are the fears of man in a corporeal form, figuratively-speaking. They prefer to attack their victims from the shadows, especially after their prey demonstrates weakness. Some of those demons are The Hidden and Scavengers.

In Diablo, enemies are also divided in 3 groups:

• Animals: take greater damage from swords/blades and less damage from blunt/clubbing weapons.
• Demons: Take equal damage from all kinds of weapons.
• Undead: Take greater damage from blunt/clubbing weapons and less damage from swords/blades. Undead are the only monster type (aside from Diablo himself) vulnerable to the Holy Bolt spell.

Items

Items are dropped from monsters or sold by the vendors. Items can be:

• Normal: Common mundane items without any special attributes. Most abundant in the game.
• Magic: Enchanted items that have one or two beneficial effects to the wearer.
• Cursed: Similar to Magic items, except that at least one of the effects is actually harmful. These become very rare past early game.
• Unique: Very powerful and hard to come across items that may have up to 6 magic bonuses (including a unique outer appearance). They grant great bonuses but might also possess some negative qualities.

A warrior prepares to enter a portal to Tristram.

Story

The story of Diablo is based on the premise of a war between Heaven and Hell. The town of Tristram is under attack by demons, and the player must save the town. As the player delves into the underworld, he discovers more about the demon Diablo, through large tomes that are read aloud by a narrator. Eventually, the player reaches the lair of Diablo and must kill him. Here is a more detailed summary of Diablo's background story:

Diablo, an incredibly powerful demon, is the Lord of Terror and one of the Three Prime Evils of Hell, who had been imprisoned in a Soulstone and buried in caverns deep beneath the town of Tristram. Though his imprisonment was meant to be eternal, the power of the Soulstone weakened over the centuries, eventually allowing Diablo to awaken from his forced slumber. He telepathically turns a nearby human, the archbishop Lazarus, into his loyal puppet. In order for Diablo to actually leave the Soulstone, Diablo needs a human body to possess. At first he tries to gain control of King Leoric, the local ruler, through his puppet, Lazarus. But, since Diablo is in too weak of a state to possess the king, he fails and merely drives the unfortunate monarch insane. He then gets Lazarus to kidnap King Leoric's son, Prince Albrecht, so that Diablo can possess and warp his body, thereby attaining physical form and freedom from the stone. At the moment of the boy's possession, his terror is so great that the boundaries between the realms are broken and parts of Hell itself seep into the mortal world and take root in the subterranean labyrinth beneath Tristram. Diablo may have a body now, but he is nowhere near his full power, so he bides his time and summons countless hordes of demons and infests the whole underground complex, claiming the new region of Hell as his own personal lair.

Soon afterwards the maddened Leoric is slain by his own lieutenants. Demonic creatures appear in the countryside as the Lord of Terror regains his strength in the heart of the labyrinth and prepares for the time when he would once again emerge in the world and seek out his brothers - Baal and Mephisto - and free them as well. It seemed to be a matter of time until the Prime Evils gained dominion over the entire mortal realm.

Then, one day, a lone traveller approaches the town of Tristram...