Azlan said:
How much and what type of new content is in the "Underdark" expansion, content that a mod designer can make use of? How does this new expansion compare in designer-content to the first expansion?
Well, you can check out
http://nwvault.ign.com/index2.shtml for lots of information, but in a nutshell... lots, and IMO loads better than the stuff from SoU.
The henchman system has been reworked a bit, supporting multiple henchmen (the number can be set with a simple scripting command). You also have
slightly better control over what they do, but they still act on their own. Also, when henchmen level up you can specify an advancement table no matter what class they take - so if you want your henchman to take different feats depending on what class it's going up in, you can specify that exactly (as opposed to only one custom one, or being stuck with the class defaults).
You can define a user-made talktable (but only one per module), allowing the addition of flavor text to any custom feats, spells, and so on that you want to make.
Class-wise, you can specify a prestige class to gain "+1 caster level", the example in the game being the Pale Master. You can only do regular progressions (every level, every other, every third), not some of the irregular ones. This can be specified for arcane and divine, so in theory you could make a Mystic Theurge type class easily enough. Also, bonus feats (like the fighter's) are now defined in a seperate table (cls_bfeat_*), able to be changed if you so desire.
Items have a new property, OnHitCastSpell. It lets you specify a spell that will be cast when you strike (weapon) or are struck (armor). This means almost total flexibility with regards to weapon and armor properties. There are also several module-level events added - OnAcquireItem, OnEquipItem, OnUnAcquireItems, OnUnEquipItem. They also provide some scripts that let you handle all of these in one script, with the same name as the tag of the item. It's not very well documented, I had to play around in some of the files to find it, and strangely I don't think HotU uses it.
Epic-level rules, PCs can go to level 40 and NPCs to level 60. Six new prestige classes (Champion of Torm, Weapon Master, Pale Master, Dwarven Defender, Shifter, Dragon Disciple). Robes. Oozes. An incredibly more functional merchant system. New spells, new weapons (whip and dwarven axe), new heads, new armors. Armor dyes. Item Creation feats, five new tilesets.
I'm probably missing some stuff. I've been mostly playing the game more than tinkering.
