I like this a lot; it reminds me of a book that my mother had (and may still have) called Giants by David Larkin (found here: [link] as the second entry). Your anatomy is fantastic and I love the mix of soft colors and the vibrant greens. I love the subtle crack lines in his skin, like rock, and the touch of the birds in the background and the mountains that sort've fade into mist; I really like that.
A few thoughts:
I have been going back and forth for a while as to what type of guardian he is. Much of the color palate trends toward earth, but with the waterfall and the Poseidon-like head dress, it clearly trends toward water. So, I'm still wondering who he really is (are we meant to even know what he is guardian of? )
His left hand feels stiff, particularly where the thumb dips into the water; it's almost as if the water is a table, or glass, and it feels too much like a hard surface; what if his hand was dipping in casually (or, is he getting up and able to make the water like that)? Also, just above that hand you have a straight line, and it looks like the end of the waterfall... if that's the case, where is the rest of his left leg? The waterfall wouldn't be that deep at the edge (I don't think...), so is his leg hanging over the falls, perhaps? The stiffness of the water shows up again under his right leg; it's too straight, I feel like it should be dipping more...
The Poseidon head dress I both like and dislike. I love how the falls come off it, but at the same time it looks too... not fake, but stiff? It doesn't seem to fit with the rest of him. Perhaps it it was less gold, more earthy. more... root-like?
It is a great piece overall; I really, really enjoy it. I kept it in my dA stack since yesterday until I had the time to really analyze it (since I saw you requested a critique). It's an excellent piece to make prints of! Well done!
Oh my god! You drew a giant man!!! It's perfect, it's beautiful! What inspired you to draw it? And in case you're wondering why I like the picture so much I am a giant man fan. Don't know why, but a very tall man is very interesting to me for some reason. Anyways, great job The colors and landscape is excellently done!