FREQUENCY: Common (Jurassic - OSRIC.186)
FREQUENCY: Common ([Tropical Wilderness Swamp])
FREQUENCY: Rare ([Tropical Wilderness Forest], [Tropical Wilderness Plains])
FREQUENCY: Common ([Tropical Freshwater Surface])
FREQUENCY: Rare ([Tropical Freshwater Depths])

NO. APPEARING: 1-6
ARMOR CLASS: 5
MOVE: 6"
HIT DICE: 30
% IN LAIR: Nil
TREASURETYPE: Nil
NO. OF ATTACKS: 1 ~ 7
DAMAGE/ATTACK: 3-18
SPECIAL ATTACKS: Step on (4-40)
SPECIAL DEFENSES: Nil
INTELLIGENCE: Non-
ALIGNMENT: Neutral
SIZE: L (70' long)
LEVEL/X.P. VALUE: VIII | 5000 + 35

The thunder-lizard is a 40 ton plant-eater found near marshes and lakes.
The creature spends much of his time in shallow water to support his bulk.
It moves to deep water to avoid carnivores. Apatosaurus ignores small
things, but it is prone to step on anything in its way (doing 4-40 points of
domage).

Man in the Funny Hat wrote: We know more about the true nature of dinosaurs including the NON-existence of the brontosaurus.
rabbi wrote: Non- existence? This is worse then finding out that Pluto is no longer a planet.
Nagora wrote: There was just a clash of names. Something else (something microscopic, I think) had already been given the name for some bizarre reason and so Brontosaurus became Apatosaurus - a change reflected in the MM, in fact. So relax, it still existed.

They had the wrong skull. The skull of Apatosaurus is slender like the skull of Diploducus, a related genus. What was called "Brontosaurus" was part of an Apatasaur with the head of a Camarasaur, so the type name is invalid according to the Linnaean System. The same thing happened with Teratosaurus: it was a mish-mash of dinosaur and thecodont bones.

- Elfdart, dragonsfoot.