Grand Theft Auto IV

You have to kill 5 DIFFERENT players in a team game, which are:

Team Deathmatch
Team Mafiya Work
Team Car Jack City
Cops 'n Crooks
Turf War

Team Deathmatch is probably the easiest one since its hard to find a game full enough in the others.

If you're boosting this, it can be done with 6 people. Just have everyone choose a different team so there are 6 teams with one person on each. That way everyone can kill 5 different people that aren't on their team.

Tardii guide is perfect but i want add more tips for u!

1-if you wanna find each other in lobby easy; do this : when you load the game bring you're cellphone(d pad up)--go multiplayer--preferences--select all setting to "don't care"
2-you have to kill 5 **different**players in *one* session

3-you have to play rank match--team death match
4-you need 6 players to its work.when you in the lobby host must choose this setting to make easy for you :
*location:airport
*weapons:rocket launcher
*set duration:1000 money
*re spawn:near
*re spawn time:1 sec
**other setting no important

*this is important:every body select "different"team(team 1 team 2 team 3 team 4....) start game:

5-everybody come together gamer who want achievement shoot with rocket to 5 players and boooom!

It took me few sessions and triple boxing to get this achievement. Here are some informations that might save you some time.

Depending on some criterias that I don't know (my guess is that it has to do with TrueSkill), you will be able or not to match with someone in ranked matchmaking. If you can't find someone, don't bother resetting your router etc... One simple way to check that it's not a network issue is to search in Race matchmaking. You will probably find everyone on first try there.
So unless you are extremely lucky, you will need 9 players to get this achievement. And not everyone is guaranteed to get the achievement.

Now how to do it:

• Each player goes in ranked Team Deathmatch matchmaking. See who is matching who then pick 2 players that matched together and take note of who was first in the lobby. I will mention them as A and B, A being the first in the lobby.

• Have A and B creating their own lobby into Party Mode. A will invite 4 players. B will invite 3 players (those going for the achievement). Then A will search in ranked Team Deathmatch. Once in the TDM lobby, B will search as well.

• Now everyone should be in the lobby. Change the game settings before starting. I suggest you to play on Prison, set spawns to close and respawn time to 1sec. You get 100$ per kill so depending on how many players are going for the achievement, you will have to set the score limit to 500$, 1000$ or 2500$.

• You may come across some issues while setting this up such as players getting kicked while joining the lobby or as soon as the game starts, and players not being able to join another player in party mode. This is why not everyone is guaranteed to get the achievement.