Relic
Ah, now we get back to some real eggs, and this map has plenty.
The first interesting things we see are images under the bridges, reflected in the water. This one says "Frank + Sue" inside a heart. My guess is Frank Pusateri did these models.
Under another bridge is this image of Shiver.
Near the end of the level we see this interesting burning hill, with some suggestive features.
And from overhead it is clearly a face. Perhaps related to the idol on Forest Heart, which was also burning.
And at the very end, we see this unimplemented unit, the Griffin, hidden inside a giant tree.
Written and compiled by Forrest.