Yes, it's the Urza's Saga style guide, from back in 1998! Before we show you some of the goodies therein, there's a disclaimer from the second page we should share with you.
This style guide is intended only as a visual reference for the environments portrayed within Urza's Saga. The text information is provided only as a means of furthering the visual concepts and in any event that the text does not agree with the visual information provided, please disregard the conflicting information and use only the visual guide. Please direct any questions regarding the style guide to the art director.
In addition to that, we should point out that Magic continuity has changed a bit in the last eleven years, so none of this is necessarily canonical information at this point. So keep that in mind. Anyway, here we go ...
... into Argoth! Today, we're going to show you the first two pages of the Argoth section, which are full of a surprising level of detail about the height of trees. If you want to see either of these next two images blown up, just click on the image.