Brilliant!

The angle of the top is off for the baby standing on it, it's too high in front, the kid would be falling backwards...

The dog is too hard edged, looking very "cut and paste," and the lighting on it does not fit with the rest of the image, since it is in shadow, yet is fully illuminated and casting a shadow in a different direction from the kid...

The waterfall is likewise lit from an entirely different direction than your light source in the sky.

Plus, your rainbow is distorted into an ellipse...

Good concept, but very rough in execution, with little attention to details and consistency.

Change the perspective on the cubes and you'll have a better entry.

1) perspective of the cube should be downwards (towards the front)
2) the boy should not have such a strong light cast, as the light ray is too far away
and the rays are on the mountains already

Thanks for all the nitpickings and suggestions, it helps me a lot in doing refinement to my entry.

Nice refinements!!! much more grounded GOOD LUCK!!!

congrats