Gears of War: Judgment
70 Achievements
1,500
58-70h
Long Bomb
Earned the You’re It ribbon on Boneyard
10
How to unlock the Long Bomb achievement in Gears of War: Judgment - Definitive Guide
After that, a one-minute timer will start. Find your Guest (he shouldn't be far away), and aim a grenade on him from a reasonable distance (50 feet is not particularly far). Once you're lined up, cancel the throw and then "blind fire" the grenade. It should go exactly where you aimed it. Once the Guest is killed, the game will end, the ribbon will display, and then the cheev will pop.
This worked for me on the first try.
But set the party type on the main menu by pressing the BACK button, to Joinable Friends.
Don't bother connecting a second controller, just fill bots to full on casual, on Boneyard, set to 50 kills or whatever you want and weapon spawns to frags and tag away. I just unlocked it this way.
Gametype: Any (except Overrun)
Type: Public or Ranked
Map: Boneyard
Requirements: Stick an enemy with a grenade from over 50 feet away
This is luck based for the most part, unless someone is standing still and not moving (someone who is not actively playing). Also it is hard to judge how far away you are. You will just have to keep throwing grenade from long distances whenever you can. There is a max amount of distance you can throw, so aim for that.
Boosting: Luckily you can boost this. Just go into free for all with a friend and once you get to Boneyard, have each other stand far back and you can both throw grenades at each other at the same time to both get the achievement.