For this achievement, you need to gain 1000 kills.
This isn't daunting or hard, just extremely time consuming. The two solutions here help out, but don't provide a method of boosting, this is where I'll take the spot
Requirements: Another Xbox with a copy of Lost Planet 2/Boosting Partner
You will want to go into Elimination, Cubed, Normal Weapons, preferably use a gun sword to make kills fast. Get your other Xbox/Partner to join, and then start the matchNote: If you are doing this during ranked matches, when everyone is in, the host should press , a menu will open up saying "Do you wish to proceed" at the end of it, don't do anything at this menu, just leave it up, the reason why is because it blocks other people from joining.
Once the match has started, get your partner to take a command post, then kill him, preferably using the Gun Sword's melee attack.
Tell them to respawn at the command post, and stand behind where they spawn, as this will be the place they will keep appearing at when respawning at the command post, continue this method until a match condition is made, then either switch so your partner gets the kills, or just keep going if you have another xbox.
I done this in around 4-5 hours, it's actually quite short.