@Whizbang Dustyboots: I actually thought that the best way to model Druid
Wildshape in
Shadowdark is to handle it exactly the way Kelsey handled the Priest's
Turn Undead. In other words, it's a spell, but one that you just know as part of your class.
Something like:
WILDSHAPE
Tier 2 (special), Druid
Duration: Concentration
Range: Self
You transform yourself and any gear you carry into another non-flying natural creature that you've seen which is close to your size with level equal to your level or less. You gain that creature's hit points, armor class, and attacks, but retain your intellect.
If you cast this as a tier 3 spell, you gain the ability to change into flying creatures and the size may vary from as small as a mouse to as big as a large bear. If you cast this as a tier 4 spell, you may shift into any natural creature from the size of a bug to that of an elephant.
If you go to 0 hit points while under the effects of this spell, you revert to your true form at 1 hit point.
(I'm not quite sure you need all the levels, but I liked the idea that it gets better, and it basically makes "Shapechange" the Tier 5 version of this spell. You could also handle this with Talents.)