Tank Force/Gameplay

Controls

 * Joystick: Use the 4-way joystick to direct the red tank (or the blue tank if you're player 2, the yellow tank if you're player 3, and the green tank if you're player 4) around each round.
 * Firing Button: Use this button to make your tank fire shots at the enemies. If one player's tank shoots another player's tank, it will push the other player backwards one small tile.
 * 1, 2, 3 or 4 Player Buttons: Push these buttons to begin the game as player 1, 2, 3 or 4.

The Players' Tanks
The protagonists of the game. Player 1 controls the red tank, Player 2 controls the blue tank, Player 3 controls the yellow tank, and Player 4 controls the green tank. They can fire up to two shots on the screen at a time, and cannot fire again until one of their shots hits an enemy tank or a wall. Unless a force field is surrounding the players' tanks, they can be killed by one enemy bullet. As said above, if one player's tank shoots another player's tank, it will push the other player backwards one small tile, but it will not kill them.

Normal Tanks
These tanks are the first enemies you encounter in the game. Their bullets travel at the same speed as yours (without powerups). One hit will kill them, and they are worth 400 points.

Speed Tanks
These tanks are like the Normal Tanks, but can move somewhat faster. Their bullets however, will still travel at the normal speed. One hit will kill them, and they are worth 600 points.

Hard Tanks
These tanks move slower than the Normal Tanks and have the same firepower. They start out gray and turn redder each time they are hit. Three hits will kill them, and they are worth 1000 points. However, unlike other enemies which have multiple hit points in this game, they will slowly regenerate their full amount of hit points if they are not hit for a few seconds.

Big Tanks
These are the slowest enemy tanks in the game. Five hits will kill them, and they are worth 1500 points; however, their flame-like shots can destroy walls with double firepower and it takes two hits to neutralize them, so it would be best to kill one when it is not facing you, because if it is facing you, you may not be able to neutralize its flame-shot in time.

Jeeps
These are the fastest enemies in the game. Unlike the other enemies, they do not get stuck in the walls and when they hit a boundary of any sorts, they change direction to continue moving. They attack by laying sticks of dynamite which will explode and destroy any walls or kill any players that are in their vicinity. One hit will kill them, and they are worth 800 points.

Rapid Tanks
These tanks move fairly slowly and warn you when they are about to fire on you, which also makes them vulnerable given that they will stop moving every time they do so. However, they attack by firing four fast-moving bullets at a time which can be very hard to neutralize and can result in a rather quick death. One hit will kill them, and they are worth 1200 points.

Tomahawk Tanks
Unlike the players' tanks and all the other enemies (which take up a space of 2 x 2 small tiles), these tanks take up a space of 4 x 4 small tiles. They will stop moving when firing but do not warn the players prior to their firing, unlike the Rapid Tanks. They attack by firing three missiles simultaneously. Each missile destroys tiles with double firepower. Their weakness is relative lack of mobility due to their slow speed and being only able to shoot downward. Eight hits will kill them, and they are worth 2000 points.

Train Cannons
These diesel multiple-units appear as bosses on the fourth, twelfth, twentieth, and twenty-eighth rounds. The first type (shown in the image to the left), have one gun turret which is mounted on the centre of their roofs; eight hits will kill them, and they are worth 3000 points. The second type (shown in the image to the right) however, have two gun turrets mounted on either side of their roofs; sixteen hits will kill them, and they are worth 5000 points. Both types fire two fastmoving bullets from their gun turrets.

AK-1
This enormous tank appears as a boss on the eighth and sixteenth rounds. It has three rotary gun turrets mounted on its roof, which will each fire two fast-moving bullets at your tank while pointed downwards. Each of these turrets takes fifteen hits to destroy; the first one is worth 3000 points, the second one is worth 5000 points, and the third one is worth 10000 points. Once you have destroyed all three of the turrets, it will explode and disappear in a cloud of smoke.

AK-2
This enormous tank appears as a boss on the twenty-fourth and thirty-second rounds. It has four rotary gun turrets mounted on its roof which will each fire a flame-like shot (which is similar to those fired by the Big Tanks), at your tank while pointed downwards. However, each of these turrets only takes five hits to destroy; the first one is worth 3000 points, the second one is worth 5000 points, the third one is worth 8000 points, and the fourth one is worth 10000 points.

Boss Cannons
Four of these enormous cannons appear as bosses on the thirty-sixth round, and attack by firing three missiles simultaneously. Each of them takes five hits to destroy; the first one is worth 10000 points, the second one is worth 15000 points, the third one is worth 20000 points, and the fourth one is worth 30000 points. However, when you kill one of them, the remaining ones will start to move faster - therefore, the last one that is remaining on the round will be moving very quickly and be very hard to hit as a result.

Powerups
Destroying enemies will spawn powerups. Like Battle City, predetermiined enemies give powerups. However, the enemies which give powerups vary per level and do not look different from enemies which do not give powerups. For an example, powerups in the first round are spawned when 5th, 10th and 14th enemy (in their entering order) is destroyed.


 * Bonus: These will add either 500, 1000, 2000 or 3000 extra points to your score. Given that points don't award extra lives in this game, they are basically only good for bragging rights.
 * Shot: These increase your tank's firepower, and their effects will wear off after you die. The first one collected allows you to fire four shots on screen at a time instead of just two, the second one collected increases the speed of your shots and the third one collected allows you to destroy steel blocks. Other temporary powerups may be affected by your firepower.
 * 4-Way Shot: This one will allow your tank to fire shots in all four directions for a short period of time, and is most effective against enemies approaching you from multiple directions.
 * Hyper Shot: This one will allow your tank to fire off bullets which move faster than normal, can penetrate walls quicker, and are very effective against bosses for a short period of time.
 * Ripple Laser: This one shares its name with a powerup from Salamander (which was the first game from Konami to use a Yamaha YM-2151 FM sound chip and a K007232 custom sound chip, but was the last to feature their "old" logo on the title screen), and will allow your tank to fire waves that cannot destroy walls but can kill enemies for a short period of time as each hit counts as up to 3 normal bullet hits.
 * Twin Shot: This one will allow your tank to fire two shots which move faster than normal simultaneously, but the shot cannot destroy steel blocks even if you've three Shot powerups. It does not stack with Shot powerups.
 * Small: This one will shrink your tank for a short period of time (which allows it to move around the rounds at a faster speed), but it does not make it any harder for the enemies to hit.
 * Shield: This one will create a temporary white force-field around your tank for a short period of time (which makes it invulnerable), but it will turn yellow when it is about to disappear.
 * Bomb Attack: This one will cause an enormous aeroplane to fly over the round and kill every enemy on the screen. The player who collected it will receive the points for every enemy. Note that players are invulnerable to enemies during this attack.
 * Timer Stop: This one will freeze every enemy on the screen for a short period of time (indicated by the clock-like song heard that is heard from the Yamaha YM-2151 during this time).
 * Force Field: This one will create a barrier of steel blocks around the headquarters, for a short period of time (which will make it invulnerable to the enemies' shots), but it will wear off. In addition, it repairs the damage done to the base wall.
 * Extend: This one will give the player who collected it an extra life. This is the rarest powerup of all, but you should not go out of your way to collect it if the headquarters is under attack.

Difficulty
There are 4 difficulty settings the arcade machine may be set - Easy, Normal, Hard and Very Hard. Difficulty affects the moving speed for the enemies and their projectiles. In very hard difficulty, enemies move over twice as fast as in easy mode. Slower enemies are affected more than faster ones.