this achievement can easily be done at the second torment room after you clear the first 3 bosses and move to the second area of the game. just enter the torment room and smack the enemies around till they are stunned. then grab them and throw them into the spike traps in the room 10 times for the achievement. you can replay the room as much as needed to grind the kills, but there are enough enemies to get it the first time.
believe this needs to be done in one playthrough..easy enogh tho