While there had been earlier action-packed (if they could be called that) role-playing games like Xanadu and the earlier Golden Axe games, they did not make shock-waves among RPG fans beyond the game system that they were intended for.
Diablo was a title that bucked that trend of mediocre success, via simplifying the burden of maintaining player characters and having a more efficient user interface while concentrating on diversifying the rewards that the player would get the longer that they play the game.
On paper, Diablo would look like yet another RPG with the usual good-versus-evil trappings, with dark, brooding themes. Even the character creation phase felt quite run-of-the-mill; the player selects a role, and then unceremoniously dumps spare points into their attributes. However, this presumption melted away once a player actually got into the gameplay system.
The first thing that a player would notice right away was the ease of playing Diablo. The game can be completely played using the mouse, with the keyboard only used for some shortcut keys. Much of the user interface can be accessed using the mouse alone (though for more efficient gameplay, the keyboard ought to be used as well).
Speaking of user interface, there is not a terrible lot to look at. The critical display items to look at are two orbs depicting mana and health, a row of icons for belt-borne items, a big one for any currently equipped spell and a space in the middle for the description of any enemies that the player may face (and hover the cursor over). The rest are buttons mainly there to be clicked on outside of battle.
Clicking said buttons on the left bring up palettes showing details like the character's stats, descriptions of quests, the map of the level and of course the menu screen. As it stands, these are really things to be checked when all is quiet and spells aren't being thrown everywhere, so it was wise for the designers to chuck them all to the left.
The ones on the right, however, may have to be accessed during battle. They bring up the inventory screen and spell menu. The spell menu is needed if the spell actively being used needs to be swapped with a specific one, but having a large panel blocking much of the screen in the middle of battle is undesirable. The game does provide shortcut keys to cycle through learned spells, but players would likely have to do a coward's run to access the menu and switch spells before going back into the fight.
The inventory screen also suffers from the same limitation, though players would have little reason to switch out weapons and armor in the middle of battle. In any case, the screen is still very, very important for a certain aspect of gameplay that will be described later.
All three roles available to the player essentially have the same types of capabilities, only with different proficiencies. While the game does allow the player to develop their characters in any way that they like, the player is better off specializing their characters; implicit bonuses that they get from a specialization-oriented development certainly encourage that. Unfortunately, this also means that the wizard, who can learn spells at a faster rate than the others, also happens to have the most interesting gameplay experience. Conversely, the Warrior, for him to be terrifically effective at what he does best, ironically would have the most repetitive gameplay (that is, endless hacking and smashing).
However, the limited role development choices are really minor setbacks if compared to one major draw of the game: the looting. There are a lot of loot to be collected, equipped and sold throughout a player's career in this game, most of them obtained through defeating boss-rank enemies or raiding treasure chests - and there are plenty of bosses and chests to go through.
(That said, most dungeons that had been already cleared would stay cleared, at least in the the single-player portion of the game. For multiplayer, they may be repopulated with monsters and loot, which is a good thing.)
Every character can use and equip any item as long as he/she meets the attribute requirements. However, as mentioned earlier, a more efficient gameplay experience could only be achieved by specializing. In other words, a player would come across quite a lot of unused loot that only other roles could benefit from - which was of course an incentive to get involved in the multiplayer portion of the game.
As mentioned earlier, the player has access to an inventory panel that shows in graphical detail the items that he/she has in the backpack or equipped on his/her person. Such a UI design was not original, of course, but it was very effectively done here; items may occupy spaces of various sizes in the backpack, but these sizes make it much easier for the player to know what kind of item had been obtained at a glance, and thus know which slots these items go to. In other words, the player did not need to go through a mess of menus to equip items, which was an irritating trait of many RPGs at the time.
On the other hand, the player would find that the backpack is a little bit too small for purposes of looting. Considering that the game uses item-randomizing scripts for loot drops, a player can end up with several suits of armor that he/she cannot stuff into the backpack. Items eventually disappear if the player takes too long to retrieve them from where they were dropped, so this limitation of the inventory system inadvertently became a source of frustration (albeit really a minor one; there can always be another piece of awesome loot to be had some time later).
With the fundamentals of the inventory and looting systems elaborated on already, it is time to write about one of the major attractions of Diablo: the loot. To describe them all is beyond the scope of this article, but it suffices to at least describe the types of loot to be gotten. There are armour pieces of many grades, weapons of just about every medieval category, an impressive school of spells to be learned from books, and elixirs that boost stats.
Also, with relevance to the statement that the player did not need to do much maintenance on his/her player character, the only items to worry about when keeping health and mana topped up are just two types of potions that can be easily purchased from the town-hub. There are no other aspects of the player character to worry about: he/she has no need for sleep, food or any kind of artificially imposed time-out that holds back the player from dungeon-romping.
The graphics of the game was not exactly ground-breaking for its time, but its engine was one of the most efficient that this reviewer had seen. There can be plenty of in-game models on screen, along with plenty of animations (though the game does disguise some of these with parallel triggering for models of the same type), yet the game suffers little slow-down. The camera does a good job of following the player character, though it has to be said that the player could not see off-screen enemies that may be firing spells or projectiles at him/her. (On the other hand, it is easy for the player to retaliate with ranged weapons or spells, until the tell-tale sound effect of the harassers' deaths occurs.) The game also makes obstacles obstructing the player's view translucent, a feature that was missing in many games that used an isometric view at the time.
The audio design is similar in caliber with the graphics design. While it has the usual grunts, growls and howls usually associated with otherworldly monsters (together with the requisite far-away pitiful screams often heard in fictional charnel houses), the game does a good job of alerting a player to any enemy skulking around in the often-dark dungeons. It also notifies the player of any incoming ranged attacks, and whether off-screen enemies had been slain by the player firing off-screen (as mentioned earlier).
The multiplayer experience of Diablo could be said to be another game entirely. The story of the game was meant to focus on only a single protagonist, but that did not stop Blizzard from creating a somewhat functional multiplayer option. Depending on the player's buddies, the multiplayer could be a smashing blast of camaraderie and wanton, hectic and fun looting.
However, it was not all sweet-smelling roses with Diablo's multiplayer. It had been recommended that new players should consider playing the game through in its entirety first before joining multiplayer sessions, due to the possibility of falling victim to the lies of unscrupulous players who would lure others to their doom. That said, the game also does not offer much protection against players who would prefer to hunt down other players instead of Diablo's minions.
Also, perhaps most damningly, the game did not have fail-safes against players who cheat by hacking and changing the statistics of their player characters and their equipment. Within a short time, the game's multiplayer became saturated with cheaters using overpowered characters, possibly breaking the game for others who did not. That said, Diablo was best played with friends who share the aim of having a genuine experience in mind.
In conclusion, Diablo was a game that streamlined the fundamentals of role-playing, while having much of its meat in the form of rewards for the player who invests time in it. It had a win-win exchange of complexities between different aspects of the game, which would later prove to be a great contribution to the future development of games within the same genre.