Namaste:
Others have made a good point about the infeasibility of brontosauri
surviving in the Plains of Prax.
I think a bigger deal would be the cultural restrictions against it. Like
most sane Gloranthas, Praxian's I believe "Fear Dragons", and dinosaurs are
draconic in origin.
Now, in my Glorantha, this wouldn't stop a Praxian Hero of some sort taming
a brontasaurus as personal mount.
--
-Santo
"Aum Shanti Shanti Shantih."