Today, GameSpot received the official beta disc for Diablo II: Lord of Destruction, the forthcoming official expansion pack to Blizzard's hit action-packed role-playing game from last year. The expansion will feature two brand-new character classes--the assassin and the druid--along with the five from the original game. In addition, it will include an all-new fifth act, which will pit players against Baal, the brother of Diablo who was never encountered in the original game. In the coming weeks, those players selected to beta-test Diablo II: Lord of Destruction will be able to try out the new character classes and also the fifth act. Feedback from this beta period will help in balancing the product before it's released this summer. Though the beta's just begun, we've already got a host of new screens from the fifth act (none of which are spoilers), as well as details on the new features in the expansion, and the new characters.

Diablo II: Lord of Destruction features a number of new enhancements, and they're already fully functional in the beta version. Perhaps the most noticeable of these is the game's support for 800x600 screen resolution, as opposed to Diablo II's locked 640x480 resolution. The higher resolution setting doesn't noticeably impair game performance on a mid-range machine, but it lets you see much more of the screen at any time and makes the automap overlay less obtrusive. The higher resolution setting even makes the 3D parallax-scrolling effect in the game more pronounced, and it helps all the bitmapped characters look sharper and smoother. Ultimately it makes Diablo II look considerably better.

To put it mildly, the expansion also includes a lot of new types of items, weapons, and armor. Some of the new item types are exclusive to particular classes. Others are exceptionally powerful, and there's even a new type of items in the expansion that can only be found in the hell-difficulty mode. The new fifth act of the Diablo II expansion, which can be accessed by a character who's completed the previous four acts, includes all-new monsters and other challenges. Many of these monsters, especially at the higher difficulty settings, are all but completely immune to certain types of attacks. This means players will need to join together in well-balanced hunting parties if they're going to make through Act V in hell mode.

Like the five character classes from Diablo II, the new classes in Lord of Destruction have varying skills they can learn, which are broken down into three distinct categories. We'll go through the assassin's skills first: traps, shadow disciplines, and martial arts.

Traps work similar to the sorceress' elemental spells, only they're typically planted in the ground and must be triggered by the enemy before they take effect. Some of the assassin's low-level traps include fire blast, shock web, and blade sentinel. Later on, she can learn to use lightning sentry, wake of inferno, death sentry, and blade shield. In general, the assassin's traps can be used offensively, though they require some tactical consideration for best results.

Shadow disciplines comprise assassin skills that improve her overall melee combat abilities for a short period of time. Burst of speed increases the assassin's movement and rate of attack; shadow warrior creates a shadowed duplicate of the assassin to fight alongside of her; and venom imbues her attacks with extremely potent poison. The shadow disciplines should help make the assassin a well-rounded fighter.

Martial arts mainly consist of special moves that can store up a charge to deal great damage upon release of the energy. Skills like tiger strike, cobra strike, and phoenix strike are charge-up moves that can make a subsequent normal or special attack inflict many times more damage than usual. A finishing move such as the dragon-tail kick can unload all this stored energy, plus pack an explosive effect.

The three categories of skills available to the druid are elemental, shape shifting, and summoning. The elemental skills are mostly similar to the sorceress' spells, only the druid focuses less on his elemental magic than the sorceress does. These elemental skills let the druid conjure forth the powers of nature. Some of the more basic skills include firestorm and arctic blast, which are fairly straightforward. Others, such as volcano and hurricane, are much more powerful.

The druid's shape-shifting abilities let him change his form into a werewolf or a werebear, and his abilities are enhanced while in this form. For instance, one skill, rabies, gives the werewolf the ability to infect enemies with its bite. The hunger skill lets the druid steal life and mana from his victims while in animal form.

The druid has a number of natural pets that he can command by means of his summoning abilities. These include a raven, a wolf, a bear, and plantlike creatures called creepers. These are multipurpose creatures that can be suitably effective to have in combat, as with the necromancer's blood golems and iron golems.

In addition to all this, the Diablo II expansion makes numerous balance changes to the existing character classes. Many skills have been enhanced to be more effective, while others have been tweaked to make them more interesting. Experienced Diablo II players will find that such changes have a noticeable effect on gameplay. The beta period will determine whether these changes are ultimately for the best.

We'll be back tomorrow with even more details on Act V and the other features in this promising expansion pack. To learn more, take a look at our collection of screenshots, movies, and in-depth previews of the expansion.