Shapechange abused?

[Quasqueton]

Using the spell shapechange, can a mage transform himself into a 200'x200'x40'(high) block of adamantium?

I met two players at a Game Day who seperately wanted to use this tactic while flying to drop on a gladiatorial opponent. According to the letter of the spell description, this seems allowed.

Both myself and the other gladiatorial game DM allowed the action, but said the fall would occur on the character's next action (thus giving the victim to be a chance to move).

I would never allow such an action in a real campaign game, but I'm wondering would this be houseruling the spell, or is there some official way to nip it in the bud?

Quasqueton

 

[Malin Genie]

Shapechange is almost irredemiably broken (and that's not a word I use often.)

By the letter of the rules you can become a Primal Air Elemental with a DC67 whirlwind, a million-ton+ block of adamantium, a Flesh Colossus with a DC56 (Ex) Frightful Presence, a DC60 (Ex) Stench which renders opponents helpless out to 300ft, and immunity to all magic (also (Ex))....

Sigh.

In an arena game in which I am participating we are limited to creatures, and HD <= caster level. This is a reasonable starting point, although I suspect it will still find a way to be abused.

 

[Kraedin]

There are ways to use shapechange that aren't abusive? That's news to me.

 

[AuraSeer]

I have a house rule to deal with the situation in the OP: if a character wants to shift into a nonflying form with polymorph or shapechange or any other kind of morph effect, he must be standing on solid ground. This prevents the adamantine block trick, the druidic hummingbird-to-rhino trick, and so on. If you want an in-game explanation, call it a safety device built into the morph magic, preventing a caster from accidental cratering.