In Gears of War 3 for the Xbox 360, you get Hail Mary ribbons for getting kills with the Boomshot from 200 or more feet away in versus matches.
The best way I’ve found to do this if you’re trying to farm Hail Mary ribbons (for the Big Explosions mutator primarily) is to setup a Private match on casual difficulty on the Thrashball map. Set all weapons to the Boomshot, and set the spawns and rounds as high as they will go. Also, it’s a good idea to set weapon spawns to After Pickup.
Right as the round starts, roadie run out to the middle of the map and switch your secondary weapon for the Boomshot. Look to your right (if you’re COG, left if you’re Locust) and you’ll see an underground room with another Boomshot to pick up. Now that you have a full Boomshot, go to the other side of the map to the balcony.
From the balcony, you can see both spawn rooms. From the door in the balcony to the spawn rooms is a little over 200 feet, so this is the key. Kill a few enemies with your rifle and force them to respawn, then stand near the doorway and blow them up right as they come out of the door.
Once you run out of ammo, you’ll find a Boomshot on the lower part of the balcony, and another back through the door in the back of the connected room.
