Ketsui: Kizuna Jigoku Tachi



Ketsui: Kizuna Jigoku Tachi is a bullet hell shoot-em-up developed by CAVE in 2002. Its primary defining gameplay attributes are its highly complex bullet patterns, its proximity-based chip scoring system, and the lock-on focus shot utilized by the player ships, Tiger Schwert and Panzer Jäger. It was developed alongside DoDonPachi DaiOuJou and runs on the same engine, as well as utilizing many of the same sound effects and explosion graphics. Both games are also notable for the switch to pre-rendered 3D models as sprites, giving the games a distinctive (and grittier) look compared to the studio's previous works, DonPachi and DoDonPachi. The story involves a group of young men who are sent on a secret "suicide mission" to destroy the EVAC Industry, an arms dealer who is developing a series of extremely dangerous weapons of mass destruction.

Gameplay Overview


Ketsui is a three-button game with two playable ships and five levels. Completing all five levels under certain conditions will trigger a second loop of the game, of which there are two variations - with one ending in fighting the True Last Boss, Evaccaneer DOOM. The scoring system involves destroying enemies up close with the Shot to increase a multiplier, and then "cashing out" that multiplier by destroying enemies with the Lock-Shot, awarding points based on the multiplier times the point value of the enemy killed.

Controls

 * A (Press): Fires standard shots from the ship and options
 * A (Hold): Slows the ship down, fires a laser from the main ship and a lock-on shot from its options
 * B: Fires a limited-use bomb, which does large amounts of damage and makes the ship invincible for some time
 * C: Auto-fire for the standard shot

Characters
Ketsui contains two playable ships, Tiger Schwert and Panzer Jäger. Tiger Schwert has a wide shot, locks onto enemies faster, and has a slower movement speed. Panzer Jäger has a straight shot, locks onto enemies slower, and has a faster movement speed. Both ships have the same hitbox size.

Resources
Ketsui uses lives to measure player health, and starts the player at two lives. On default settings, an extra life is granted once at 20,000,000 points, and again at 45,000,000 points. Specific strategies also grant the player additional extra lives (see Hidden Extends)

The player starts off with three bombs at the beginning of each life. Additional bombs are granted by killing specific enemies.

The player is given three bombs after respawning from death, regardless of how many bombs they had before. Those playing for pure survival are advised to use a bomb if they feel death is unavoidable, in order to maximize how many bombs will be available to them throughout their playthrough.

Loops
Following in the footsteps of the previous releases by CAVE, completing all five levels under certain conditions will trigger a second loop of the game. There are two variations of the second loop, called the Omote loop and the Ura loop. During the second loop, the scoring system entirely changes and requires different play strategies in order to maximize your scoring potential. (See Second Loop Scoring for more information.) Reaching the Ura loop is the only way to fight Evaccaneer DOOM at the end of the game, otherwise the game will end after destroying Evaccaneer in Stage 2-5.

Omote Loop


 * Beat the game with no continues
 * Sum of deaths + bombs used is less than or equal to 6

Ura Loop


 * Beat the game with no continues
 * No-Miss and No-Bomb the first loop
 * Earn at least 120,000,000pts during the first loop

In both versions of the second loop, enemies will fire significantly denser bullet patterns, and will also release a barrage of revenge bullets when destroyed (blue bullets in the ura loop, red in omote).

Scoring


Killing enemies awards points. There are two multipliers that can increase the amount of points given, known as the boss multiplier and the enemy multiplier. The boss multiplier is equal to the value of all chips picked up during the stage, and is used when killing the boss, and the enemy multiplier is used when killing enemies with the lock-on shot.

Maximizing the amount of high-value chips you pick up is the key to increasing your multiplier. Killing enemies up close with the standard shot awards higher value chips - up to five, depending on distance. After this, a brief countdown is initiated, shown under the multipliers. During this countdown, killing enemies with the lock-on shot will also award chips, of the same value, regardless of distance, until the countdown runs out.

This cycle - killing with the standard shot to start a countdown, killing enemies with the lock-on shot to cash out the multiplier and gain more chips, and repeating once the countdown runs out - is the primary building block of Ketsui's scoring system.

Stage Completion Points
At the end of each stage, the boss multiplier is used to award additional points based on the number of bombs and lives remaining. Each life (including the current life) grants five hundred points times the boss multiplier, and each bomb grants fifty points times the boss multiplier.

Second Loop Scoring
In the second loop, enemies no longer drop chips on death. Instead, the game adopts a simpler scoring mechanic based around enemy revenge bullets. Specifically, when enemies are destroyed, each revenge bullet that spawns adds 1 to the multiplier. In the omote loop, sealed bullets do not contribute to the total, but in the ura loop they do. The multiplier is cashed out in the same way as before, by destroying enemies with the lock-on shot.

The higher the enemy is on screen when destroyed, the more revenge bullets are released, so killing enemies quickly is encouraged for scoreplay.

Hitboxes
The player's hitbox is 2 pixels wide and 3 pixels tall (4x6 on hardware, due to the rectangular pixels of the PGM). Despite there being several different bullet types in the game, all bullet hitboxes are in fact just a single point, with no thickness at all - the player is hit when the point falls inside their ship's hitbox.

In the second loop of the game, the player's horizontal hitbox is shrunk by half a pixel.

Empty Locking
Full details: Empty Locking

Killing enemies with the standard shot grants chip items and starts a countdown, and killing with the lock-on shot during countdown grants additional chips on top of cashing out the multiplier for the enemy killed. However, '''the chips granted when lock-on killing enemies in countdown are not spawned by killing the enemy itself. They're instead spawned from the explosions after the enemy is killed.''' This means that receiving the lock-on chips from an exploding enemy does not necessarily require that the enemy was killed with the lock-on shot.

By killing an enemy with the standard shot to start a countdown, and timing a switch to the lock-on shot so it's active by the time the enemy is exploding, the game will grant the chips for standard-killing the enemy, and also grant the lock-on chips during the enemy's explosion.

Switching to the lock-on shot to gain additional chips during an enemy explosion, without actually killing it with the lock-on shot, is known as empty locking.

Empty locking allows the player to save multiplier while acquiring lock chips from an enemy, or in the case of air zako it will be used to gain more multiplier than otherwise possible (shot chip + lock chip, vs just shot chip). '''

Stage 3
Destroying all pieces of the midboss battleship before killing it will grant a 1up item. Bombing prevents getting the extend.

Note that the turret that shoots pink bullets in a circular pattern (18, right) will destroy all of the other pieces on death, so saving it until last is recommended.

All pieces must be manually shot down by the player in order for the requirement to be satisfied.

Stage 5
Just before the Midboss, two "clones" of the player ships will fly onscreen. If they are killed without bombing, an 1up item is awarded.

Video References
Video index for Ketsui