Waterfall
I found a photo of a waterfall in the net and used it as my waterfall. I applied the texture to a plane and let it
move in the Y axis.
waterfall
As for the smoke, I did it in houdini and export it to make it into sprite atlas. I placed the smoke at the start
of the game , just below of the bridge and on top of the water fall just below the clouds. Waterfall usually produce a mist that is why I placed it at the start and at the end of it.
This is a reference picture of waterfall mist.
Rainbow
For rainbow, I searched in the net for a nice photo of a rainbow but couldn't find one which
is how I wanted. So i took the best looking photo of a rainbow I can find and used it
in photo shop to tilt it to the right. After which I export the rainbow to after effects and
animate it to move from the bottom left to right.
Then I export it to houdini and make it into sprite atlas.
Rainbow