So, I've played and beaten Demon's Souls so I'm not coming into this game completely new but I have a couple of questions for you. I played Demon's Souls as a Royal (I know, I know) and I enjoyed using the magic. From what I've been reading though it looks like the Pyromancer might be better than the sorcerer in this game for my tastes. Can the pyromancer still learn all the spells or only fire spells? If so, what stats should I focus on. Basically what's the +/- of each of those two classes and how should I build them?
Pyromancy is a class of spells that has no equivalent in Demon's Souls, unlike Sorcery and Miracles which are fairly analogous to their Demon's Souls counterparts. The main distinguishing feature of Pyromancy is that it requires no stat investment to use, with its power instead being determined entirely by the level of your Pyromancy Flame, which is the Pyromancy equivalent of a Catalyst or Talisman. You can spend souls at any of the game's three Pyromancy Trainers to improve your Pyromancy Flame and thereby make your Pyromancies stronger.
Pyromancies are primarily short-ranged offensive spells, including fireballs of varying power, melee ranged bursts of flame, and several variations of the Firestorm spell with which you're probably familiar from Demon's Souls. It also has a handful of buff spells with either limited applicability (such as the Flash Sweat spell which reduces damage from fire-based sources) or some sort of downside (such as the Power Within spell which increases your attack power but also applies an effect causing constant continual HP loss). It doesn't have any form of long-ranged offensive spell or any form of healing, and the number of uses of each spell you receive is more limited than the number of comparable Sorceries or Miracles.
On the whole Pyromancy is essentially the spell school for non-Sorcery or Miracle-oriented characters. Absolutely any character build can use Pyromancy effectively provided they spend the souls to upgrade their flame, making it an easy choice for any build that isn't focused on either Int or Faith. It's worth noting that, unlike Demon's Souls, you don't have separate slots for equipping different types of spells, and Sorcery, Pyromancy, and Miracles all share a common pool of equip slots, making Pyromancy less popular for heavily Sorcery or Miracle-focused characters.
Like Demon's Souls there are no restrictions on what you can learn and equip based on your starting class. In time any character can do anything. The Pyromancer is a popular choice for first-time players because it has a well-rounded set of stats, the lowest starting Soul Level in the game, and begins the game with a Pyromancy Flame and the Fireball spell, which is tremendously useful in the early going. In time you can develop the character into any build you please and leave Pyromancy behind entirely if you so choose.
Secondly, what's this about humanity? Does it work the same as demon's souls like being in spirit form and such? Does it really matter?
Humanity is a complex mechanic. It's simultaneously an item, a sort-of stat, and a quasi-currency.
Like Demon's Souls, you've got two forms you can be in: human form and hollow form. They're roughly similar to the body and soul forms of Demon's Souls. In human form you can invade and be invaded and summon co-op allies. In hollow form your only interaction with the online portion of the game consists of viewing and leaving messages. Unlike Demon's Souls there are no further penalties to being in hollow form, you've got full HP at all times and there's no need to sacrifice a ring slot to an equivalent of the Cling Ring. The only real malus to being hollow is that you're ugly as sin. Wear a helmet.
To change into human form you need to expend a point of Humanity, which can be gained by assisting other players in co-op, killing other players as an invader, or by using an item called, appropriately-yet-confusingly, Humanity. When you die you'll revert to hollow form, and all of your Humanity will be lost. If you recover your bloodstain you will regain all of your Humanity along with your souls. Note that you do
not lose Humanity in item form when you die, giving you an incentive to not use it as soon as you get it.
You can have up to 99 stored Humanity, which in addition to being used to change into human form is also a sort of stat. Stored Humanity slightly increases your defense, increases item drop rates, and also grants increased attack power to certain weapons.
I think that's a decent overview of what Humanity is without delving too deeply into esoteric functions. It's a sufficiently complicated mechanic that giving a good summary of it is kind of difficult. Suffice it to say that some amount of playing the game will be necessary to really get a firm grasp on how it works.
I know about being patient and not worrying about souls and all the good stuff but is there any particular words of wisdom for someone who hasnt' been following this game at all that I should be looking out for or not doing (ex: not using the boss level demon's souls in demon's souls because they should be used to level up equipment or used to buy spells, etc)?
The single most important piece of advice I can think of for new players is this: Do not hit people in barrels with a weapon to free them.
Roll into the barrel instead.
Pretty much everything you've learned about boss souls is also applicable to Dark Souls, though they're no longer used to learn spells and the equipment made from boss souls isn't as powerful on the whole as it was in Demon's Souls.
