Trying to figure out how to manipulate Terrain as a game feature(?)

So I'm making a fighting game and I'm really digging the new Grass Terrain in studio and I really want to implement it into my game. What I'm trying to do is when a Player smacks another into the ground the terrain makes a crater. I also want to know how to restore the Terrain after a little bit. I have ZERO KNOWLEDGE in this. I tried finding an API/ Tutorial but I couldn't find any. If anyone could help me figure this out it would be much appreciated.