Let's come up with an amphibian race!

That's actually better. What else do we have left? What are the creatures doing? And what about the crocodile?

Some people don't like the crocodile, and that's it. But, as I said, there's a crocodile god in Egyptian mythology. I would still keep it. But we need to come up with an alternative for it, just in case. A Basilisk and a Wyvern (where can we go without them?) instead of the crocodile and the turtle.

Added 2 minutes later

That's actually better. What else do we have left? What are the creatures doing? And what about the crocodile?

Yes, probably "Mother Earth" won't work after all. After all, this spell should be available to all races, and only this race can call the earth "mother". So, we should keep "Earth's Core".