So this is the condensed version of a conversation going on between a few of us. This is the first serious exploit found in DDO so far as I can tell. As much as I would love to take credit for this, SHAGGSTER was the one that actually came up with the idea. I worked with it for awhile and this is what i found.
First you need to have a proficiency with a heavy or light repeating crossbow. Then you have to purchase 2 of them and put them both in your hotbar.
basically you target the monster use first bow, manually fire two shots (with right mouse or other bound key), then switch to other, manually fire two shots and then switch back to the original xbow. Once you switch back to the original crossbow it will have a full load of bolts in it. If you use all three then you will have to reload it again even if you switch crossbows.
When going back and forth you can fire off 120 shots in one minute. If you try and go any faster than that you will mess up and have to reload after you fire all three shots. So here is the breakdown of damage.
1D10 damage per shot at 120 shot per minute comes to : 120-1200 plus 10% of the time you will get a critical hit.
SO you can do anywhere from
240-1320 damage per minute at level one. Which includes the extra damage from criticals
I have never heard of anyone being able to put out this much damage no matter what level. at lvl 10 a sorcerer can only put out 960 damage to one target using all the their mana, but that takes 56 spells so it would be well over a minute. This is a monster exploit. Use it while you can.
Oh and i almost forgot. The first time i did this i got a different kind of bug and was not able to hit my target even though he was standing in front of me. When i switched back to my other xbow and then turned on the auto attack i kept firing over and over again without reloading but I wasnt able to hit anything. The dice didn't even roll and my bolts didnt leave my inventory. To fix this I took out a melee weapon and swung it a few times. Then when i switched back to my xbow it worked just fine again. So heads up if you get a bug like this it is easily fixable.
I would have to say that this takes alot of practice. Tabbing through monsters as they die and continuosly doing this on a loop is a feat in itself. But after 2 hours of practice i was able to kill just about everything before it got to the party. At the end of butcher's path we had 100 kills 67 of which were from me and i am a ranged user. We had a wizard and another fighter with a 2hander. He didnt do much because the monsters didn't really even get in range. I can only imagine using this in an outdoor zone with xbows that had additional elemental damage. If you are able to keep the monsters at a distance and have an understanding party that doesn't rush into battle you will clean house.