Massacre
The massacre experience bonus in Diablo III is bonus awarded to characters who kill a large number of monsters in a single hit, or a very short time frame.
Another similar bonus may be awarded for a [kill spree]], when a character scores multiple kills in rapid succession, rather than just a huge number of kills almost simultaneously.
Background
The D3 Team has said that inspiration for Diablo III includes adventure games and action games. In the case of the Monk, they have even taken inspiration from traditional arcade Streetfighter-style games, and the massacre experience bonus comes from these types of games.
Diablo 3 is set out to be very fast paced, and things like Health Globes are added to keep the pace high, while still requiring a measure of skill to play. Killing enemies one at a time isn't very hard, but it's part of the gameplay with "easy to learn, hard to master". If you want the extra added bonuses, you need to figure out how to kill enemies fast and in a rapid progression.
This massacre feature will likely also be tied in to Achievements at a later point in the development.
Experience bonus
When you kill a series of monsters in a short timespan, you get an one-off experience bonus that follows a very simple pattern: 5 experience per kill.
The Experience bonus received seems to be related to the character's level, which just makes sense, but still linear. This is one example, with an assumed progression at an unknown level:
(A) = Assumed
- 5 Monsters = +5 Exp (A)
- 6 Monsters = +10 Exp (A)
- 7 Monsters = +15 Exp (A)
- 8 Monsters = +20 Exp (A)
- 9 Monsters = +25 Exp (A)
- 11 Monsters = +30 Exp
- 12 Monsters = +35 Exp (A)
- 13 Monsters = +40 Exp (A)
- 14 Monsters = +45 Exp (A)
- 15 Monsters = +50 Exp
- 16 Monsters = +55 Exp
- 17 Monsters = +60 Exp (A)
- 18 Monsters = +65 Exp (A)
- 19 Monsters = +70 Exp (A)
- 20 Monsters = +75 Exp
There has also been reports on 11 kills giving 24 exp and 12 kills giving 28 exp, so it could very well be as simple as +1 exp per kills per level after 4 kills. That would make the above list a lvl 5 character, and the 11/24 - 12/28 example a lvl 4 character.
Development
The massacre feature was first shown at the BlizzCon 2008 gameplay demo, and has not changed much since then, as of September 2009. Jay Wilson said in a press conference[1] that the idea came from when the team tried to give the Experience Shrine and Monster Shrine from Diablo II a new twist, making it more like a game mechanic than the only two shrines people cared about.
Shrines have since been re-implemented into the game in the latest BlizzCon 2009 demo.
Media
You can find pictures in the Diablo 3 screenshot and picture gallery:
Witch Doctor massacring monsters.