Carmageddon: Max Damage

To get this achievement you need a total of 66 online kills across all modes. The best way we found was to set up an online race since that gives you the biggest time limit. Fox and Hounds is the best for getting the 30 online wins but doesn't really work for kills since the tag keeps changing every time you hit another car. However, using the following method will help you to rack up the kills very quickly.

Have the player getting the kills pick the Cadillac, and the other player something fragile such as the rocket car or buggy. Player 2 parks with their nose facing a wall, then player 1 drives into them from a medium distance. This results in a kill almost every time, and player 2 will respawn right next to you making it even easier. The below clip shows just how quickly it will go by using this method

For this achievement, you have to rack up somewhere between 50-75 online kills/wrecks, I didn't keep exact count, and it seemed to go by fast today.

Other guides online suggest you can set up your own private games with options to set kill limits and time limits, but I have not found how to do this, but if you can get into a Car Crusher with a friend and trade kills back and forth (5 per match each plus 1 for whoever is going for the win towards the MP MegaPeeps), that'll get it done in a couple hours.