*New Tier 3 Boss added. Is there no one good enough to win?
*New Ball type: Archangel. An extremely rare but valuable ball, the Archangel glows yellow to give you hope in bleak times. To activate one, remove a Redeemer from the board and use the Redeemer's power to remove the Archangel. After doing this, your next cursor click spawns a Tunneler at the top of the column your cursor currently resides in. Seeing that Redeemers are rare and that Archangels are always to be a boon, you may remove an Archangel at any time by clicking on it, but you cannot use it to create a Tunneler in this fashion.

Update 1/25/06 AI Changes:

*There is a known issue with the Boss Challenge incorrectly deploying its Tunneler move that awards the player 250 points each time, typically resulting in a total bonus of 2000 to 3000 points. Since the maximum score in Boss Challenge is 1500, the issue is serious. The issue has not been resolved, and it only occurs on certain machines. To mitigate the issue until it can be further researched, the point award for forcing the AI to use its Tunneler cheat is reduced by 125 points each time it uses the move.
*Tier Two boss added. This guy is quite nasty. Enter the password you earned from the original boss to face him. Note that due to balance changes with existing bosses, a password given by a certain boss becomes invalid one version after serious changes are made to the boss who issues the password. You will be notified if your password is in jeopardy.

Boss Challenge mode added to the game. The options for this mode cannot be changed. A passcode feature with higher levels of play might be added later, but for now this mode features an intense battle against an almost impossible AI foe. The boss is extremely nimble, and has been known to get very lucky with Tunneler spawns. He styles himself immortal, but dealing him a close call with death will net you 250 points. If you can survive to 1500 points, you win. Good luck!

*AI now makes use of cursor wrap.
*AI now attempts to form larger groups by favoring groups made of colors less represented on the board. The effect compounds itself resulting in a large accumulation of one or two colors, making big groups. Thanks to Greg for the idea!
*Threat computation changed so that groups in columns that don't extend above the top half of the board receive the same amount of threat. Previously the score distinguished between a column with, say 1 ball in it from one with 3. This has been corrected so in low-threat situations the AI makes choices based on other factors.

Update 1/22/06:

New! Rudimentary AI implemented for more gameplay fun and craziness. The AI is fairly challenging, and especially excels in games with quick drop times, such as Turbo Deathbattle. Check it out by unchecking the "Human?" option on the configuration page.

A bit about the AI: The AI interfaces with the normal, human-input methods in the game, that is, the game and board classes do not know the difference between a human and a computer player. As a result, the AI cannot cheat or do anything that a human could not do. The AI's speed in removing groups is only hindered by the speed of its cursor, which has been locked at 0.2 cells per 10 ms, a value lower than the default human cursor speed.

The AI's primary task and chief difficulty is to choose which balls to remove from the board. It does this as follows. First, the AI creates a list of groups on the board and assigns a score to each. The score of the group is based on four factors, its size, its distance from the AI's cursor, the amount of rare balls in the group, and the so-called "threat" that the group poses (balls in columns that are almost full to the top score large threat and those that are in almost empty columns score little threat). These four categories are weighted, and although the weights are often changed in testing, they are currently (in descending order) threat, size, rarity, and distance. The value of the group's threat is also squared after it is computed.

Besides computing a point value for every group on the board, the AI also filters out certain groups that are toward the bottom. The idea is to let the AI pass over groups at the bottom because 1) they aren't important to remove so long as that column is not in danger, and 2) they can be used to form larger groups if they are left alone. In that spirit, each row in the board has a tolerance level and unless the game is about to be lost, a group in that row must exceed the tolerance level to be considered for removal. The computation for the tolerance level is complicated, but it includes both the size of the group and its ball content.

This complete, the AI targets the group with the winning score for removal. If all groups were filtered, the AI brings the cursor to the center of the board and waits. The AI's overall intention is to remain largely idle while the board is less than 75% full and then spring into action to save the game. Since large groups were likely built up during this idle phase, the AI is capable of scoring a large about of power meter points while clearing the board.

The AI is also capable of using Redeemers effectively to remove Blockers and to trigger stuck Nukes.

The AI is currently not capable of strategically removing groups about to be lost to Assassins, Moles, or Tunnelers, nor is it able to recognize situations where it is advantageous to remove a small group to connect to larger groups.

Important Notes:

1. The sensitivity of the game controls can be adjusted in the configuration options. The cursor can be set to wrap around the edges.
2. If the applet window is reloaded but the browser is not closed (system restart in the case of IE) the game may remember its previous configuration settings.
3. Special thanks to Kevin Glass for use of his Keyboard class! Check him out at Coke and Code

Game rules:

1. Players one and two use WSAD and the arrow keys, respectively, to move the cursor around the screen.
2. Players one and two use space and enter, respectively, to "click" with the cursor to remove the balls it currently selects.
3. Removing balls scores points and clears board space. Remove large groups to charge your power meter (see rules 6-8)
4. The game continually adds balls to your top row, starting at 10 second intervals.
5. If you have a ball in your top row when a new batch is due to be added, you lose.
6. Compete with your opponent by sending nasty balls to his/her side of the board. To do so, charge your power meter to 100%.
7. The power meter is charged based on the score achieved in a single group. For example, removing a single group of eleven balls charges the power meter much more than removing two separate groups of six. Whenever you charge your power meter, a floating text label appears above your cursor to tell you how much power you got out of that group.
8. If you have more than 100% power, every cursor click will drop balls on the enemy until your power is below 100%. Typically this means the click that put you over 100% will expend your power (since it takes a full 100% to drop a row on your enemy), but if you remove a sufficiently large group you can score more than 200% with that click and have more than 100% left over. Use this to your advantage, since you can time the ball drops perfectly.
9. The types of balls enabled changes as your score increases. In general, as score increases, the balls the game drops on you become more beneficial and the balls you can drop on your enemy become more deadly.
10. As your score increases, the rate at which balls are dropped by the game increases. How high can you get your score and still survive?
11. At every multiple of 1000 points, your screen is cleared.

Special features:

1. An interactive tutorial to learn to play. Click "Help" on the main applet. Use WSAD to move the cursor and space to "click" when an interactive portion is displayed. The tutorial covers all the ball types that are well-tested.
2. Multiplayer gameplay!! Compete with your opponent by working hard to make the largest groups possible. Only large groups will charge your power meter and let you add nasty balls to your opponent's side of the board. As your score increases, the balls you drop on your enemy become more deadly!
3. Rich customization options. Click "Configure options" on the main applet and let the tooltips guide you to the perfect game, or choose one of the default configurations from the drop-down pane. For your reference, the list of ball classes available is Ball, Ghost, Blocker, GravityBall, Knight, Nuke, Stone, ScrewBall, Tunneler, Freezer, Multiplier, Redeemer, Assassin, and Mole. If the configuration options window is not opened before the game is begun, the last configuration is used. If there is no previous configuration, tournament rules are used (the first default configuration).
4. To see all the classes in action, choose "All Unlocks" in the default configurations drop-down. Some will still be rare! At a minimum, please check out Nuke, Tunneler, Assassin, and Mole.
5. Cool animation on GAME OVER and on balls removed with Tunnelers or Nukes.
6. Cool flashing text label on Nuke, Redeemer, and Assassin balls.
7. Cool floating text label when power meter is charged. Rainbow when multiplier active!
8. Sometimes silence is golden...
9. No animals were harmed in the production of this game.

Be sure to check out Greg's site to play his awesome game and to get links to other Jaw Breaker clones!