In fact, even before getting my hands on the LBBs within the last decade, I always had a gut feeling that something was "weird" about the 7th-9th level spells -- while the 6th level list has the stark "powers over life, death, and eternity" (death spell, reincarnation, disintegrate, control weather, anti-magic shell, permanent geas and invisible stalker, etc.) the higher-level spells have often fiddly and complicated powers that are hard to see why they're better. Of course, looking at Sup-I answers the mystery: the LBBs contain just levels 1-6, and it was Sup-I that introduced all of levels 7-9 as tacked-on afterthoughts.
Let me look at some of those "new" Sup-I spells, mostly the ones in levels 1-6 (the ones I potentially play with) -- asking some pointed questions about whether anyone ever found use for them, or if they're basically firing "blanks". I won't look at the entire later history of these spells; generally they didn't change very much, perhaps due to the fact that they were under-powered and no one was breaking the game with them (so, little in the need for errata or fixes). Perhaps I can observe a few categories for these Sup-I spells as follows:
- Low-Level Spells that Are Clearly Powerful. This would include the addition of shield, magic missile, darkness, strength, web, and mirror image (all 1st or 2nd level). Several of these are considered must-haves for wizards of any level, in some cases contending to push the best attack/defense spells from the LBBs out of use (sleep and charm person). These all became canonical identifiers of D&D, of course, and it's really hard to imagine the game without these key additions.
- Low-Level Spells That Aren't So Great. This would be ventriloquism, magic mouth, and pyrotechnics (again 1st-2nd level). Ventriloquism at first doesn't even seem like it should require magic; maybe a thief or entertainer skill. I've never seen magic mouth used by a player; it's more of DM plot device (waits eternally to deliver some information). And pyrotechnics starts a Sup-I'ism in not having a single clear game effect, but instead a series of "maybes" that require interpretation at the table ("A multi-purpose spell... either a great display of flashing, fiery lights and colors which resemble fireworks; or he can cause a great amount of smoke... overall effects of this spell depend on the size of the fire used to cause them", none of which have in-game definitions or effects; p. 22).
- Mid-Level Spells That Are Questionable. Namely explosive runes, rope trick, suggestion, and fear (3rd-4th level). Of these, fear seems to be the most useful (replicating the Fear Wand from LBB Vol-2, p. 34); the others seem strangely over-specific and limited. Suggestion I wrote about earlier (link); it seems deficient to charm person at 1st level. Explosive runes seems like another DM-protection element (it could just be an added one-liner in the scroll curse table); I've had players use this on a piece of paper and then parley with monsters to trick them into reading it, which seemed to cut against the grain thematically. Rope trick also seems to me an oddly over-specific representation of the (mythic?) "Indian rope trick" stage magic (link); I think I might prefer a more general "step into a small, short-term, extra-dimensional hiding spot" than the whole climb-up-a-levitating-rope business.
- The Mid-Level Filler Series. These would be monster summoning and extension series. These spells reappear at multiple levels with a Roman-numeral tag on each in the sequence. The monster summoning spells (I-VII, levels 3-9) refer the user to the random "Monster Level Tables", which is useful, and mechanically concise since the element already exists. But I find it to be rather tasteless game design since I can't wrap my head around (a) how the monsters get into the possibly-enclosed space with the PCs, (b) why it totally disregards whether monsters of that type exist in the dungeon, (c) why the monsters just wander off afterward, etc. The extension spells (I-III, levels 4-6) may be flat-out the weakest magic ever; they only extend some other lower-level spell by 50% duration, and if it didn't do the job in the first couple turns, are the next few going to make any big difference? Case studies: (a) I'd rather use a duplicate 1st-spell and double the duration than burn a 4th-6th level spell for only 50%; (b) the only thing that extension II does better than I is to add specifically 4th-level spells to the possible targets; (c) extension III, while in the spell list, doesn't even get any entry in the text descriptions (okay, fixed in the corrections insert at the back of the book). It almost seems like these spells were just filler to round out the mid-level lists to 16 entries each.
- Higher-Level Spells That Don't Get Used. Here I'm thinking legend lore and repulsion (at the 6th level; compare to other "life or death" magic above at the same level). Legend lore "seeks to gain knowledge of some legendary item, place or person", requiring DM interpretations on (a) what counts as legendary, (b) exactly what knowledge is gained, and (c) whether it even works at all (note the word "seeks"). This spell seems like a Rorschach inkblot test for the players and DM, possibly the vaguest spell I know of in D&D; and it also has randomized casting time, from 1-100 days (the only spell in OD&D, of very few in any edition, with multi-day casting time). Repulsion "enables the user to cause objects or entities to move in a course opposite from their intended course towards him", which seems like a restatement of the confusion spell as written in Chainmail (there only 4th level), and seemingly defeated as soon as enemies think to say "I move away from the caster". I've never seen this spell get used in play, ever.
- Spells Whose Power Comes from Disallowing Saves. This kind of burns my chaps, because it seems like a clunky rules hack that totally contradicts Gygax's other rants that "everyone gets a chance" (see AD&D DMG defense of saving throws). It's inelegant in that later rule sets need to start adding a stat-block line dedicated to keeping track of whether each spell is "Yes" or "No" allowing a save. Personally, I don't honor it my games. These spells include (some overlap here): sleep (by errata in Sup-I), magic missile (not explicit in Sup-I, but ruled that way in later sets), explosive runes, ice storm, and everything in the new levels 7-9 (p. 25: "Spells with no saving throw unless otherwise indicated!"). In particular, ice storm (4th level) looks deficient to fireball (less range, only 30 points max and no increase per level, whereas fireball does 42 max damage for a like-level caster and goes up from there), until you note the parenthetical point that "saving throws are not possible"; 1E added a variant sleety usage that caused no damage, but blindness and a possible slip-and-fall. Hacky!
I guess the only other thing in Sup-I at these spell levels that I'm looking at is the errata for the charm person and charm monster spells, actually the first thing in the list, which introduced the unique recurring save schedule by Intelligence or Hit Dice (and was carried forward through all later editions up to 3E). Even that seems unnecessarily complicated, table-heavy, and unfocused, wasteful design effort; the best version is in Moldvay's Basic D&D where he wisely edits it down to just three categories (day, week, or month). Lastly: detect magic is given a range and duration for the first time, but then why not also do so for read magic and read languages, that suffer the same lack at the start of the Vol-1 list?
So there's my personal rant about the Johnny-come-lately, frou-frou, fiddly magic-user spells and alterations that appeared in D&D Sup-I. While many of the spells at 1st-2nd level are must-haves, the ones at mid-levels are either vague or questionable or clearly worse than pre-existing options. And the new higher-level spells generally cheat and complicate the system by prohibiting any saving throws, so I don't like those, either.
What are your thoughts on those later-added spells; do you agree? Is there anything here that you found absolutely indispensable, to which I've been blind? Have any unusual interpretations that clearly "fixed" one of these spells for you?