You need a friend to grab this Halo: Achieve Achievement, officially called Workers' Compensation. You have to run over an enemy with a forklift, but it doesn't work with traditional enemies. The best way to do this is in a Custom Firefight match.
You or your friend need to host the Firefight match, then go to options. You want to go through Elite settings and Spartan settings, select the Basic Traits option. Click on the Shield and Health option, switching the shield multiplier to No Shield. This way the elites and Spartans in the game have no shields during combat and to harm their health.
Then choose the court card. This location is the fastest to find Forklifts.
When the map and shield options are properly adjusted, make sure your friend is a Spartan or an Elite, and you are the opposite. After that start the game on the easiest difficulty.
From there you want to find the forklift on the map. The first is on the left, where the Spartans appear in the game. It's hidden behind a large metal crate, but not too hard to find. After that, you or your friend have to jump into the other and then knock the other down. The person who performs the kill receives the reward, and then the person who dies must resurrect and do the same.
You don't need to do the realization on this map, but the yard has the most obvious ones to find. There are two on the map, one on the left and one on the right.
