Rumbleverse

It seems complicated but this really comes out easy in the final rings. I recommend activating the superstar mode when you are on top of a building and throw yourself to where the crowd of players is to do more damage and drop the achievement.

In my case, the achievement was given to me when I was on top of a building and when I saw that my friend was in combat with several players, I did what I mentioned above to receive the achievement. I don't know if it is necessary to do a certain number of damage but I recommend doing more than 500 damage since when I did less, it didn't unlock it.

I hope you find my method useful and thanks for reading.

FOR PEOPLE HAVING ISSUES WITH THIS ACHIEVEMENT:

This achievement is a little confusing on how you get it with its description but from what i experienced you need:
Reasonable height
Have to have the elbow drop land on the enemy/friends hitbox and just the splash damage

I say friend as I ended up hitting my partner in trios with the elbow drop instead of the enemy and it popped (Needs to be confirmed by others but the clip below is when i got the achievement)

What id recommend is at least trying to elbow drop (X Button) on enemies/possibly friendlies and making sure you are landing on them and not near them.