Hi, everyone

My question includes three points, two simple and one may seem weird:

- I have a strong will to know how to make rain & fire effect. I know it's very easy ,but I can't set the proper values ,especially for the fire effect. Also, I want the code for a rain effect (I did it but caused some lagging) that is the fastest and the most efficient


- The second point is as follows: I've a part of terrain that's supposed to be a volcano running. Actually, it's not running of course ,and I want to make it run or ,for another instance, I want a part of my terrain texture to move making some running river or volcano effect.


Thank you for reading