
I read that thread, and thought about the spell. First off, a lot of people at DF these days seem not to know the rules as written. Or they read into it more than was intended. Or skew it to how they believe it should work. So I'm going by just the spell as written and the game core rules.
Side note: the spell is called reincarnate for wizards but is called reincarnation for priests (in both 1E and 2E). I'll use the names interchangeably, because they're the same spell in most ways. I just sometimes use one term or the other, forgetting which is which.
I have to say, I can't off hand remember ever using the reincarnation spell in my games. Actually, we did once, for a monk. But that was a very unusual circumstance that was played as part of the ongoing backstory and it was used differently than as detailed in the rules. Long story. Anyway, I just don't see the purpose of the spell. I'll explain why.
First, when a character dies and the player wants to continue playing that character, he (or more accurately, the party) has only a few options.
1. Find a priest who can cast raise dead or resurrection
2. Find a wish spell to wish him back
3. Find a druid or wizard who can cast reincarnation
There is a fourth option, where the party begs divine intervention directly from a deity, but that would still count as a resurrection and would be such an exceedingly rare circumstance that it might ever happen once in 20 years of gaming. So we won't count that as it would still fall under the category of a resurrection or wish albeit cast by a deity instead of a mortal.
So with the spells wish, raise dead and resurrection, what is the ultimate effect? The player's character, the PC, is brought back to life and continues to be played by the player. That is the sole purpose of the spell - to bring back to life the character that the player had been playing prior to the character's death.
The 4th spell, reincarnation, does not achieve that goal. The player does not get back the character he was playing. It's totally different, in almost every case. Looking at the wizard options for the reincarnation spell in 2E, more than half of the results of reincarnation (9 out of 16) are not classable races, i.e. they cannot have classes (trolls, ogre mages, goblins, et.). With the priest spell reincarnate, only 3 out of 20 listed options (the 21st option is DM's choice) are classable races (elf, gnome, human). So in most cases, the reincarnated person comes back as an animal or a monster, not the same character originally played and in most cases not even a being realistically able to go on adventures. Seriously, has anyone ever played a badger character in AD&D, in any campaign ever? Can you imagine a reincarnated stag going on a dungeon crawl? Coming back as an evil monster or animal means the character no longer exists, for all practical purposes.
So if the spell does not accomplish the goal of bringing back the PC the player used to run, and since the vast majority of options create monsters or animals that cannot have class, gain levels, use items, or even enter dungeons due to their size, what use is the spell? To create pets out of your colleague?
Another issue is the fact that the reincarnated character, if it is of a player character race that qualifies for his previous class, only retains 1/2 his levels. That's better than starting a new character at 1st level, although the reincarnated character is now going to be the weakling of the team - not much better than a henchman or hireling. Although I admit I've never required a player whose character has died to roll up a new 1st level character because it makes no sense, for example, to have a party of say 6th or 7th level characters and your new character is 1st level. He's a henchman then, not a PC. So new characters come in at the average level of the party or at the same level as the lowest member of the party.
Anyway, back to reincarnation. If the newly incarnated character is of a new class, he begins at 1st level, which as I just explained is ridiculous and not worth bothering.
The spell, as written and used, is essentially useless. People have come up with what I'd call "tweaks" to the spell, but all of them seem ridiculous when thought about. People talk about anthropomorphic badgers and raccoons. But that is not what the spell says it does. It does not create "werebadgers" or "werestags", for lack of a better description. You do not get Rocky Raccoon from Guardians of the Galaxy walking upright and speaking English - you get a furry little four-legged raccoon who cannot speak human or humanoid languages. And even if you did something like that - imagine the sort of ruckus it would create in a campaign. A party walks into the bar with a raccoon standing on its hind legs speaking human tongue. Or a bear doing so. Or god forbid you bring a stag walking on its hind legs ordering a round of ale for the party!


People also argue about the CON restrictions on resurrections and whether reincarnation counts. I would argue no, and I don't see how it can be argued that it does. The CON score represents the character's physical health - his physique, immune system strength, stamina, endurance, cardiovascular health, etc. Each death erodes that health so that the next time you die, it's harder to come back because your body has lost some resilience. That only makes sense, because a body that has been dead for days or weeks has rotted some. It's decayed, so when it's raised it doesn't have quite the genetic integrity it used to. The spirit or soul is called back, but the spirit does not get weaker, otherwise it would cease to exist upon the last death. The soul inhabits the body, and the body gets more worn out by each recycling - each death and subsequent resurrection.
When the character is reincarnated, it forms an entirely new body, brand new. It has no wear and tear. It has no previous deaths. It has a totally different CON score. So why would it count?
Someone at DF misquoted the 1E DMG, claiming the character has the same CON score. That it not what the 1E DMG says. It gives an example of a badger that can become giant sized, getting max hp and a CON bonus, and the intelligence of the original character. Clearly the CON score is the CON of the badger, not the previous incarnation of the character. The only reason the INT of the original character is kept is to explain how it can have the memories of the original incarnation.
So no, the new incarnation does not get the CON score of the previous incarnation.
Which brings us to another issue. According to Hindu and similar religious beliefs, a reincarnated person does not gain memories of his previous life. The soul contains those memories, but the person cannot remember his previous life except in bits and pieces in very rare circumstances. That's not, however, how it works in AD&D. And that means a new set of problems.
What is the point of having a human character reincarnated as a badger with all the memories and INT of his human self? Would that badger not now still crave beautiful women, the thrill of the hunt, fine clothing, gold, fine wine and good food? Or imagine a reincarnated stag. They graze on grass and grubs. A previously human character who remembers how good wine was, or chocolate, or a good steak, will no longer be able to enjoy the foods he used to enjoy. And unless you're playing in one of those depraved modern games

As I'm thinking about all this, I'm thinking the reincarnate/reincarnation spell needs a lot of fixing because it's a strange spell that seems to cause more problems than it solves and lacks any real purpose in the game.
I've always wanted to write my own 3rd Edition AD&D PHB and DMG, and call it "AD&D Ultimate Edition". That's what I call it now, how I play. I took all the best of 1E and all the best of 2E (usually it boils down to - do I want to use the 1E or 2E version of this rule or mechanic?) and mixed them together. Mostly it's things like adding back assassins, half-orcs and monks that were taken out in 2E, or calling demons and devils what they are, not tanar'ri and baatezu.
I think the reincarnate/reincarnation spell would need some serious work.
First, I now prefer the 1E method where druids have their own unique spell list and clerics have their own (with new unique ones for priests of specific religions, as shown in the FR Gods books). It makes druids different. I've always loved druids and part of that love is that they don't worship gods - they worship the force of nature. It makes them very different than any other class.
I would remove reincarnate/reincarnation spell from wizards altogether. They can do so much as it is, no need for them to have this spell. Clerics can cast healing spells as well as raise dead and resurrection. Druids can cast some healing spells and reincarnate. Wizards can cast none of those. It would be called reincarnation, not reincarnate, just as we call the spell resurrection, not resurrect (nouns, not verbs).
I think I would restrict it to reincarnating PCs as humanoid races. I do see some charm with the idea of a druid reincarnating a follower (perhaps a druid acolyte) as an animal, because it fits the class in a sense - the character becomes a different player in the whole of nature (he was human, now he's living in nature as a badger, etc). But that seems a bit meaningless in game terms. What I mean is, that would serve nothing more than an interesting piece of backstory. The spell has to serve some mechanical purpose in the game. So I would re-create the list to allow only humanoid races. I do like the possibility of the reincarnated person possibly coming back as a different race, so perhaps a human coming back as an elf, gnome, goblin, or orc. I would, since we are keeping the INT of the original character, allow the new character to retain any previous class he had. I think that not only makes sense, it's logical. Why would a human thief, who knows and remembers all the techniques for picking locks, picking pockets, etc., not be able to do so simply because he's in a new body - say a gnome or a goblin? Yes, you can argue there is a neuro-muscular aspect to it (muscle memory, such as drawing a gun, or a knife, or picking a lock), but it seems far more logical that any skill is retained. Can anyone honestly argue that a human who had the rope use NWP and knows how to tie knots would not be able to tie knots in a rope after being reincarnated as a goblin or an orc? So likewise, the idea of the character not remembering how to pick a lock or cast a spell is ridiculous.
Also, there is the roleplaying aspect. Now, I would say that the alignment of the new character would remain the same regardless of the new form. Why? Because his morals, his outlook, his memories, his worldview would all be the same. It's the same spirit coming back in a new body. It's the spirit, the mind, that creates alignment, not the body. For example, Drizzt. Drow elves are evil, but he is good.
And imagine the roleplaying possibilities. Imagine an ugly half-orc (or an even uglier full orc!) who used to be a paladin, but got reincarnated. He still has his holy and ethical/moral outlook. He still strives for law and goodness in keeping with his god's wishes. But now he's ugly and not as charismatic. Sure, high CHA is a requirement for paladins, and as an orc surely his CHA would not be the same. Amongst humans. But his CHA might be very high amongst orcs or goblins. So now he has his looks working against him while proselytizing for his religion amongst humans, but working for him when he preaches to orcs. It sets up so much roleplaying and drama that I could easily add 3 more pages to this admittedly very long post!
So in summary, I would allow reincarnation to bring the character back in a humanoid form (human, elf, dwarf, gnome, halfling, orc, half-orc, goblin, hobgoblin, etc). He would retain the same class and skills and level in his class which he previously had, and the same alignment. None of this coming back at 1st level or at half your old level nonsense, no coming back as a pet animal or an anthropomorphic stag or some such silly thing, etc. That way, the spell does work, but also presents likely very difficult challenges to the character. Does a human who is now a dwarf really feel comfortable living in the gloom underground? Can he stomach powerful dwarven ale? What if he was previously an elf? He's going to like the taste of dwarven ale? Is the now-dwarf character attracted to dwarven women? Or does he still lust for human women? A lot to think about!
Good lord, I'm all typed out! Haven't written such a rant in a long time! What do the rest of you think?