Will said:
Treebore: By that logic, a spell that obliterates continents is fine, because they earned it and it's jaw dropping.
I really don't see how 'well, 9th level spells are powerful' is a valid response. Now, pointing out how powerful specific 9th level spells are, that's a bit more useful.
Disjunction, for example, is pretty powerful. One good question would be 'can Shapechange do something similar, and do it more often?' I'm not aware of any Disjoin monsters, but that would be an example of comparison.
Will,
I view your response as I don't want to compare apples so I'll throw in how rediculous it is to compare apples to chow mein to prove how rediculous it is to compare apples.
9th level spells are powerful because it took you long time to "earn" the right to be able to cast them, plus you are playing a character that is supposed to be powerful. If you feel high level characters should be castrated instead of becoming powerful that is your game. My game says you become powerful.
Plus Shapechange is a progression of the polymorph power chain. There is an inferred progression within the game mechanics from the lower level polymorph spells to this "ultimate" polymorphing spell. It is an earned, and deserved, culmination of magical power.
I have been able to deal with it just fine as a DM. Yes, it is a powerful spell. It is very versatile, and can be frustrating to deal with. It should be, it is a 9th level spell. Such a power should not be "easy" to handle.
Just because a DM has problems handling such a spell doesn't mean it is too powerful or broken, it just means the DM needs to become more resourceful themselves. Resourcefullness isn't nerfing the spell to being something you can handle, it is learning in game strategies that are effective in countering such powers, which is what other high-level characters can/should/would do.
So DM's should adapt and overcome, not just wimp out and re-write a spell because it is "too hard", broken, or whatever. Shapechange has had nearly 30 years of playtesting. It isn't broken, it is just a challenge to a DM's skills.