Thanks in advance.
I've got some other things irl I'm working on, so perhaps some other folks here could answer better than I will here, and in more detail.
But to make a long story short, the difference between the MotP and Planescape is that the MotP draws heavily upon Planescape material, but doesn't go into the same detail, nor the depth that Planescape did. The MotP is Planescape light essentially, distilled down to its base elements, and not always distilled properly in places. It loses lots of the flavor that Planescape had.
Planescape was much less focused on combat than it was RP, and the role and concept of 'belief' and the place of belief in the multiverse.
Planescape 3e will eventually fill the gaps that the MotP didn't fill, or fill properly or in as much depth and detail. The website is at www.planewalker.com
While the MotP mentioned them briefly, it couldn't do justice to the City of Doors, Sigil, or the factions or The Lady of Pain in the paltry space is was able to devote to them. Planewalker will eventually have a full writeup on The City of Doors, the factions, the planes, and a continuation on the plotlines from 2e Planescape post Faction War and with 3e rules.
(Faction War was the 2e module that was the culmination of many of the extant plots in the setting, specifically in Sigil itself. It also ushured in a good many changes into the power structure of Sigil, and the roll of the factions in Sigil and on the planes at large.)
And that is just the difference in monsters.
I don't have time to go into a massive description of planescape, but I do have to say that the detail given to many places is exquisite. The characters in planescape are some of the most detailed in the history of D&D. If you can get a chance to look at a copy, you should check out Uncaged: Faces of Sigil. It is a good example of the attention to NPC-NPC interaction that exists and makes a truely fantastic setting really come to life.
And my 2 cents is PS was about bringing the Outer Planes, long the exclusive playground of high leved to "epic" adventurers, to everyone. The setting made it possible to play characters from 1st level to the ungodly. It also departed from your traditional dungeon crawling, hack and slashing style worlds. It was an exotice breathe of fresh air. From the artwork to the very language you were introduced and immersed in something completely new.
If you can imagine a world like medieval London peopled with strange Jim Henson-esque creatures (ala Dark Crystal, Labyrith, and the Storyteller) you'll begin to get it. The defacto illustrator for the setting was Tony Diterlizzi and his work is really inspired by Brian Froud (who did all the Henson stuff I mentioned). If you follow fantasy art and illustrators you'll know what PS did for Tony (like Dark Sun did for BROM).
The 1e MotP read like stereo instructions (no insult intended to Jeff Grubb) or astronomical texts. The 3e MotP is basically the watered down version of the more than 30 planescape boxed sets, adventure modules, and campaign supplements.
The Wheel of Ideas just kept turning all the time.
Yeah, complicated; but that is what I liked about Planescape.
It was a harsh world of binding law.
It was freedom and expression unleashed.
It was the struggle for the greater good.
It was the corruption of all under evil's will.
It was the soaring, endless heights of Mount Celestia.
It was the endless emptiness of the Gray Waste.
It was saving the multiverse from mad half-dead gods.
It was sitting in the tavern flirting with a girl with antlers.
It was, and shall be again, or so the yugoloth's tell...
We'll have the full faction chapter released in the immediate future, as soon as the editing is done, and there's one minor section we're still mulling over, and two factions are having new art made for their faction symbol.
That said there's unreleased stuff thats finished sans editing, but that may wait for the other chapters to be finished, *cough*Sigil*cough*. :D
We've slowed down slightly here the past month for a variety of reasons. I'm plastered with real life work, so thats my excuse, and most of my contribution won't see the light of day till later on in the release schedule likely.
And whats this about planewalker.com not being user friendly? Problem with browser compatability or just site design? I can rather easily poke the webmonkey and withold her bananas till the problems are fixed. ;) Lemme know here or by private message and I'll let her know if its something she should look at.
Now as far as what books to get... 'Faces of Sigil'; 'In The Cage: A Guide to Sigil'; and 'The Factols' Manifesto' and 'Faces of Evil: The Fiends' are probably the four best books there are. [Edit: Forgot to add Planewalkers Handbook and the original setting box set]
Then there's the Monstrous Compendiums, if only for the artwork by Tony DiTerlizzi.
Next I'd look for the Ethereal, Astral, and Inner Planes books; then move onto the box sets such as Planes of Law, Planes of Chaos, Planes of Conflict (on ebay if you're a rich man), 'Hellbound: The Blood War' .
After that, the modules for the setting are all very good, especially IMO Faction War (some will differ with me here), The Great Modron March, Dead Gods, and 'Doors to the Unknown'.
If you don't want to pay the prices for some of these on Ebay, nor do you want to pay for the ESD's of each, I'd look in hobby shops like Hungates which tend to have older gaming books that never sold. I've found a number of PS books there stuffed on shelves and usually reduced and in great condition. Used book stores on occasion might have them too. And some gaming stores may still have them around, though most stores had all of their PS stuff bought out shortly after the PS line got canned by TSR.
And whats this about planewalker.com not being user friendly? Problem with browser compatability or just site design? I can rather easily poke the webmonkey and withold her bananas till the problems are fixed. Lemme know here or by private message and I'll let her know if its something she should look at.
Well, the Planewalker.com logo doesn't need to be tiled in the upper left corner, it leads to having 1 1/2 copies of it sitting up at the top there. like so. Also, on the pages such as "features", which currently have no content, there's 3 and 3/2 copies of the logo, and the layout is messed up. Don't get me wrong, it's a wicked cool logo, I just don't need to see it six times per page. :p
Also, I'm not sure why you keep a list of the article titles in each section on the left sidebar, when they're pretty clearly printed with a synopsis just slightly to the right of the left sidebar, in the main section of the page.
Also, if you're going to use CSS, please move to a tableless layout. That alone would solve a lot of problems. Poke your webmonkey with a "get with the times" stick and make her life easier. Much easier. Way much easier. CSS tableless layouts take MUCH less time to deal with than a bunch of tables. They're faster too.
It'd be nice to move the stylesheet information out of the body of the page too, and just link it externally. Then you don't need to clutter the html with stylesheet information a hundred times over. No more "" crap in the middle of the html.
Oh, also, you don't need an ampersand in front of the first get variable in php. Not that it's a problem, it's just an ugly nit.
Basically, all you know of Planescape from the MotP is the environments of the different planes, their cosmology, and some of their inhabitants. And speaking of the inhabitants, there's a lot. To briefly cover the primary planeborn races that really rule the planes, there's the celestials: further broken down into aasimon (some in MM, I think more in MMII), eladrin (some in MMII), guardinals (some in MotP, some in MMII I think), and archons (some in MM, some in MMII). Then there's the lovely fiends: baatezu and tanar'ri ("devils" and "demons" from just about any creature book), yugoloths (MotP), and gehreleths (FF). A web supplement to MotP had write-ups for the modrons, the lawful neutral beings. MM covered the chaotic neutral slaadi. The rilmani (true neutral) were in the Fiend Folio, I think. Then the Inner (Elemental) Planes had elementals and a whole lot more. I may have forgotten some, but you get the idea: these are just the planeborn races.
The idea of belief is, as everyone has mentioned, a huge part of the game. Your character's motivation, loyalties, and philosophies were very important. The Outer Planes are realms of pure thought, so their inhabitants' beliefs and willpower can change them. For example, sixteen towns on the Outlands each exemplify one of the Outer Planes and quite frequently physically shift onto their corresponding Outer Plane because the ideas of the people who live there become too far from neutral. Therefore the land that they live on becomes a part of that plane.
The most central city of the planes is Sigil, which lies on the inside of a huge ring that floats above the Outlands. Aside from that little oddity, the city looks much like a fanciful antique London. Until the events of the Faction War (though to a degree it continues), the city was dominated by the factions, which are all detailed on planewalker.com. These are a perfect example of the way in which your character's ideas are critical. Most characters belong to a faction, and their belief in the faction's philosophy gives them power. Not all factioneers are the same, though. You might be a member of the Athar, but do you try to go around and convince people that the gods are frauds, or do you grab an epic sword and try to slay some demi-deities? Do you think that all the gods are just advanced mortals, and simply short of divinity, or do you think that they are manifestations of the Great Unknown and are abusing their station?
The most central thing about Planescape is the idea of the infinite. There is no limit to the size of the planes, and some would argue that there is no limit to their number, either. Therefore, you can find anything. Just because the Abyss is an abhorrently violent a awful place beyond description doesn't mean that people don't live there. Mortals have build cities there (and some immortals have, too). They're just not sitting on prime real estate and probably don't love their home.
The best thing for you to do is to check it out. www.mimir.net was the old planescape site and has a huge amount of flavor information and background. It's a wonderful site, but it's a tad short on game mechanics (and any that are there were made for 2e) but hopefully planewalker will soon fix that.
Real life just gets in the way *way* too much....
What I see when I read the various PS stuff is the love that was poured into making the various books. They are MUCH more interesting then any of the other settings I have read (Underdark, Forgotten Realms and DL).
If you want a typical fantasy world stick with FR, if you want a crafted item, go for PS.
I think the biggest difference in the MotP from the PS books is the lack of character. Reading the MotP is like reading a textbook. Things are just presented to you as they are. Most of the PS books are written from the perspective of a planar blood of some sort or other. They portray the facts about the planes in a concise and easy-to-understand way, but they also give you these facts in such a way that make it easier for the reader to become absorbed by the world. This character makes the planes seem like more believable places, alternate worlds that really do exist. The MotP lacks this character and, to me, makes the planes seem like just another fictitious world.