Red Dead Redemption

The problem with this achievement is that you run out of enemies pretty fast, so if you kill enemies yourself a couple of times because they are attacking you, you don't have enough of them left to score an assist on.

I've noticed that you can get assists on your friend's and your own HORSE. Just join a public free roam, enter a hideout - preferably Fort Mercer b/c your enemies are all inside the Fort and you can get this one on the outside without them getting in your way (you might have to take out the ones on top of the entrance).
Now all you've gotta do is whistle your horse in turns with your friend, shoot the horse in the leg and have your friend shoot it in the head afterward. The killer has to kill with one shot, otherwise the achiever won't get the assist.
You get assists for shooting both your friend's and your own horse.
This way, you can "create" your own enemies, so you can't run out of people to shoot.

Hope this helps...

CONFIRMED THIS WORKS!

speaking from experience doing the pike's basin method with a buddy for 2+ hours with no success, we used the horse method in 15 minutes! BIG THANKS to FLOSTA32 for posting his unique solution! wish his guide was up when i attempted this for myself 4 months back. :D

join a public free roam session and posse up with a buddy. set your way point to fort mercer in the rio bravo area of new austin. once you’ve both arrived, activate the gang hideout by approaching the fort. once the gang hideout is activated, as long as you stay outside, but in the vicinity of the fort and can see red enemy dots on your map/hud, you’re good. the enemies are inside the fort, but you might want to take out the shooters above the entrance.

tips that made this work fastest for us:
1) i called in my horse and mounted it (hold right bumper to have it stand still).
2) my buddy (who needed the achv) shot it once in the chest with the bolt action rifle.
3) i quickly jumped off my horse and one-shot it in the head with the winchester repeater.
4) if your horse tries to run away, just keep whistling for it to come back or quickly mount it.
4) make sure the person that needs the achv sees "you assisted gamertag" after each kill.
5) rinse and repeat. achv will pop up after 10 assists. you do not need to finish the hideout.

I just got this achievement the other day. I thought it was going to be a pain, but a friend and I found a reasonably easy way out.

First off, PUBLIC FREE ROAM. Like every other achievement, we kept wondering why it hadn't unlocked yet before we realized we were in a private free roam. Derp.

Second off, snipers are the key. You probably have one already, you get the Rolling Block pretty early in MP. If you don't have one, I THINK the westmost gang hideout in Mexico has one as it's weapon. Get that, go sit on some white ammo boxes for a while to get plenty of reserves, and head out to your favorite gang hideout.

**********************TL;DR MEAT AND POTATOES**********************

The easy way to do this, in my opinion, is for you and a friend to have sniper rifles. Stay far back and call out your targets. Have the achievement hunter shoot the target in the leg, and the helper finish them off. A leg shot will not kill with the sniper, it will only knock them over. You can easily be far enough back with the sniper that the enemies won't shoot at you while you do this.

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A little more info if you're still reading - choose any gang hideout you prefer. We did Pike's Basin, because that's what we normally run when we're XP farming and we are familiar with it. I'd recommend it, a friend and I both got the achievement in one run.

If you do Pike's Basin, just take it easy as you go through the level, stay back, and call your targets. One solid tip - when arming the north-east bomb, after you've set it, immediately run up the hill to the west of the bomb (most likely the direction you came from) and take a right so you go to the top of the basin. Three guys will spawn there, just take them right out. Now, sit at the top of the basin and look down into it. Six guys will run out from the left, and as they probably haven't seen you, will all stand in a cluster in the middle of the basin. Even after you open fire, they normally won't scatter, and you'll have six assists right there.

Thanks to my buddies Griffy the Kid and MrMoJoe we all three completed this yesterday. We simply went to Teroso Azul Hideout and picked a target i would shot them first and them they would finish the enemy off. The key to gettig an assitt is to shoot the enemy once and then you friend has to shot them one more time but they have to kill them with the one shot. If you shot them and then your friend shots them more than once you will not get the assist. They must kill them with one shot after you shoot them.

If you don't like shooting each others horses or each other for that matter and the sniping isn't going too well. One last method I'll mention that Wyman87 and discovered was to start Pikes Basin try to callout and shoot at the same guys at the first area (the place you spawn after voting to replay) after clearing out the first section with the cows in the fence simply have the person who wants the assist shoot a cow in the leg or a low power repeater to the body and the other person shoot the cow in the head and it counts as an assist. There should be around 6 cows or sometimes more to start out and still have 2 crates to blow up and plenty of guys so it should be a breeze from there.

I got this in about 10 minutes. I joined two other people in Pike's Basin and led the charge from a distance, shooting enemies with a Winchester Repeater, then the other players would following soon after and kill them, scoring the assist.

For short range combat, a gun like the Volcanic Pistol was also fine - as long as you weren't aiming for the head the same theory applies.

Just make sure the other players follow soon after - no more than say 60 seconds. I found in some instances while I may get $2 for the assist, it wasn't counted. It is only counted when you see the message in the HUD (e.g. sjpsjpsjp assisted MacWhyte). Do this in a big enough hide out and it's a cinch.

After wondering for a while how I was going to get this achievement, I stumbled on quite a simple way to unlock it.

Step One - You need a hideout with a good amount of enemies - I used Nosalida but anyone with 25+ enemies will do the job.

Step Two - Make sure that someone else is attacking the same hideout, either a boosting partner, a posse member or a random. They will be doing the killing.

Step Three - Pick a weak weapon - I used the winchester repeater - make sure you have plenty ammo.

Step Four - Set your aiming to casual.

Step Five - Attempt the hideout, for each enemy you lock on to with LT, nudge the RS down a little and shoot them in the legs. They should fall over but not die. When they get up they should be limping and then your partner can finish them off and get you the assist.

You can keep a rough count by keeping an eye on the bottom left of your screen and looking for 'you assisted ****' or by looking for the green $2 appearing. Please note that this count doesn't always tally for the achievement for some reason so more than 10 assists 'may' be needed.

This is my first attempt at a guide so go easy please :)

Adding onto flosta32's solution, the horse method still works as of July 2015. Make sure you go into a non-glitched lobby (where you are able to call your horse), and go to the entrance of Pike's Basin, by Mcfarlane's Ranch. You and a buddy take turns calling your horses. The person going for the achievement should shoot the horse with the Springfield rifle directly on the body (not the head, not the legs). Your buddy will then use the Springfield rifle or the Bolt Action rifle and shoot it either in the head or body (not the legs). Repeat 9 more times for the achievement.

Remember, the assist only counts if the game specifies you assisted the other player. The achievement will pop as soon as you get the 10 assists, so you multiple people can go for the achievement quickly.

If you don't like boosting, this is an alternative solution for this achievement.

Start off in multiplayer friendly free roam. Head to Tesoro Azul. Once there use the Rolling Block Rifle and snipe enemies in the legs. This will not kill them, but they will be one hit away from dead. Do this to 10 enemies. Once you have a bunch of gimps, start randomly inviting people to posse. Set your marker to Tesoro Azul. The new posse members will come and start shooting everyone, getting you assists.

Tips:

1) Play when the servers are semi-crowded. This will give you a batch of players to invite in case people don't accept your posse invite. If there are too many people on you will have a hard time getting 10 gimps before someone comes starting to shoot up Tesoro Azul with or without an invite from you.

2) It doesn't matter how much you die. It is much more important to make sure you don't kill the enemies, just wound them. Everything persists through your deaths.

3) Invite low level players. It is actually pretty difficult to get more than seven gimps before the reinforcements are called in for this hideout. So, once you have the most you can get invite the lowest level player into your posse. Don't invite anyone else. They will hopefully head your way and kill off some of the original gang members but not be good enough to cream the reinforcements before you can snipe some kneecaps.


Happy hunting!