Dungeons & Dragons first supplement, Greyhawk, raised the game’s highest level spells from 6th level to 9th. None of Gary Gygax’s players had reached the level required to cast the new spells.
Tim Kask remembers that as he and Gary worked on the Blackmoor supplement, they figured players faced little chance of even reaching level 9 or 10. “This was before the gross inflation of XP’s and the corresponding levels. The highest level player in Gary’s Greyhawk campaign was level 7 or possibly 8 at that time, and they had been playing more than any other group with the possible exception of Dave’s.”
Greyhawk’s high-level spells served non-player characters and indulged Gary’s love of systematic cataloging—the same inclination that drove him to create a plane of existence for every alignment.
At level 9, Gary stashed outrageous effects from fantasy. Shape Change duplicated a scene from the movie Sword in the Stone. Wish, Time Stop, and Gate came from popular imagination. Astral Spell came from the Doctor Strange comic.
Most of the level 9 spells boasted game-breaking effects. Shape Change let casters gain the shape and abilities of any creature at will, over a duration of hours. Gate could summon a god. Wish seemed to allow anything. Astral Spell probably helped you spy, but you needed to read Doctor Strange to be certain.
To Gary, these spells stood above the players’ reach, reserved for scrolls, liches, and legends.
Gamers played D&D with more passion—and less disciple—than Gary ever expected. Player characters raced past level 17 and gained those once-legendary spells. Now the spells marked either (a) where D&D stopped playing like D&D or (b) where players rolled new characters. All of Gary’s players retired their characters at levels in the mid-teens.
Gary wrote that he designed original D&D to challenge characters between 1st and 16th level, and not 17th-level characters with their level-9 spells. Eventually, the 9th-level spells prompted the fifth-edition designers to mark a new tier for 17th-level PCs. See The obvious innovation in fifth-edition Dungeons & Dragons that no designer saw before.
When heroes oppose the lich queen, what does she wish for?
By the time Gary designed Advanced Dungeons & Dragons, he knew that 17-plus-level PCs bedeviled DMs everywhere, but he kept spells like Wish and Shape Change. Gary aimed to keep the elements of his original game. Instead of eliminating troublesome spells, he imposed limits. Shape Change now consumed a 5,000 gp. jade circlet. The description for Wish now warned, “The discretionary power of the referee is necessary in order to maintain game balance.” I wish I had known that before my players wished for level-infinity PCs. Astral Spell added some baggage about silver cords and continued to discourage casting through obfuscation.
Third edition coped with the legendary spells by adding limitations. Wish stopped granting Wishes and now offered a page-long menu of magical boons. Shapechange lost a space and added hit die limits. Deities and unique beings could now ignore the Gate spell’s summons. As for Astral Spell, I must have missed the issue of Doctor Strange that explained its value.
Fifth edition continues the strategy of containing overpowered spells with long, limiting descriptions. Wish once appeared in 4 lines, now it spans a half page. Shapechange grows almost as much.
Why do these spells remain in the game, even though Gary Gygax never expected players to enjoy free access to them? In part, I blame tradition. Fourth edition eliminated Wish and its kin, but players rebelled against a game that cut so many familiar ingredients.
Designers struggle to capture a sense of wonder appropriate for the game’s most powerful spells while keeping spells playable. Meteor Swarm never aggravated any DMs, but a cluster of fireballs just feels like more of something from level 3. Of Gary’s legendary spells, Time Stop ranks as the best. It combines an epic feel with a manageable effect. In some future revision of the game, I hope to see Wish retired to legendary status and replaced by more spells in the mold of Time Stop.
The page that you linked to with “Gary wrote” doesn’t have a post where he talks about the intended levels of characters that D&D is meant to challenge.
By and large, players never do access these spells. We’ve all seen the statistics. 90% of characters never get over level 10. Only about 2% make it to level 17. A grand total of 1 published campaign goes long enough for players to get there, and I use the term “campaign” loosely.