Dangerous Seed/Gameplay

Controls

 * Joystick: Use the 8-way joystick, to direct your current ship around the screen; they'll always be moving forward, but you can direct them anywhere.
 * Firing Button: Use this button to make your current ship fire shots at the enemies; if the arcade owner has set that "Shot" option dip switch to either "Rapid" or "Full", you can press and hold down this button to make your current ship fire off continuously, but if he has set it to "Manual", you cannot.
 * Special Weapon Button: Use this button to make your current ship fire one of its special weapons at the enemies; they can possess a maximum of four at a time. Alpha-Ship has Ring-Lasers and Beta Ship has Melt-Missiles, while Delta Ship and both of the Combined Ships has Hyper Bombs.
 * 1 or 2 Player Buttons: Push these buttons to begin a 1 or 2 player game.

Alpha Ship (αシップ)
Energy: 3, Special Weapon: Ring-Lasers; If Alpha Ship is unlucky enough to get destroyed in any of the first four stages, Beta Ship will make an attempt to get through. Despite being the smallest one of the player's three ships, its shots shall become the most powerful, as the game progresses.

Beta Ship (βシップ)
Energy: 4, Special Weapon: Melt-Missiles; If Beta Ship is unlucky enough to get destroyed after taking over from Alpha Ship, Delta Ship shall make an attempt to get through. It is slightly larger than Alpha Ship in horizontal width, and is therefore easier for the enemies to hit with their bullets.

Delta Ship (γシップ)
Energy: 5, Special Weapon: Hyper-Bombs; If Delta Ship is unlucky enough to get destroyed after taking over from both Alpha and Beta Ship, your game will be over. It is the same size as Beta Ship in horizontal width which means it's just as easy as it for the enemies to hit with their bullets.

Combined Ships (合成シップス)
If you made it through the first four stages with all three ships intact, they will combine into the large ship with an energy of 12 on the left; however, if you were unlucky enough to let Alpha Ship get destroyed in any of the first four stages, the two remaining ships will combine into the smaller, medium-sized ship with an energy of 9 upon the right. Both of these combined ships have Hyper-Bombs as their special weapon, and if you were unlucky enough to let both Alpha and Beta Ship get destroyed in any of the first four stages, Delta Ship will not have anything to combine with, and must try to make it through the next four stages of the game alone - and, those two Kanji characters in their Japanese name are also read as gōsei.

Turtles (タートルズ)
Each of the ships can gain up to four special weapons by destroying the Turtles and then collecting the powerups that they leave behind; the green Turtles shall only appear when you are in control of Alpha Ship, the blue Turtles shall only appear when you are controlling Beta Ship, and the red Turtles will only appear when you are controlling Delta Ship (and either of the two Combined Ships, during the second half of the game), but the yellow Turtles will appear regardless of which ship you are currently controlling and will leave an Energy-Capsule behind when destroyed, which will restore some of your ship's lost energy when collected. If you have the maximum of four special weapons, the green, blue, and red Turtles shall leave a Special-Bonus powerup behind when destroyed, the point value of which will increase as the game progresses - however, the yellow ones shall leave a Hyper-Booster behind when destroyed, which will make your ship fly right to the end of the current stage, and return to normal speed for the boss battle.

Enemies who appear on Stage 1
BOSS: Triple-Eye (トリプルアイ) - This enormous three-eyed spider attacks by firing orange balls, that transform into webs, from his three eyes (which you will have the chance to destroy with your own shots for 50 extra points apiece); therefore, it is advisable to aim for his "arms" first (which are both worth 2000 points when destroyed) as he uses them to shield his aforementioned eyes (which are worth 10000 points when destroyed). Once you have destroyed his eyes, he will no longer be able to fire any more orange balls from them, so you should then aim for his tail (which is also worth 2000 points when destroyed), to finish him off - and once you've done so, he will emit a scream of death and explode, and you shall also receive 20000 more points as that text of "DESTROYED THE TARGET!!" appears on the screen. It is also possible to aim for one of the two groups of three legs, on his sides, to defeat him instantly (without having to destroy his "arms", eyes or tail); however, he, and all other subsequent bosses in the game (apart from Danger-Seed himself) will retreat if you take too long over defeating him and the text "MISSED THE TARGET ENEMY!!" will appear on the screen (you shan't incur any penalty, if this happens).

Enemies who appear on Stage 2
BOSS: Strike-Ants (ストライクアンツ) - This enormous pair of ants attack by firing projectiles from their claws and needles from their noses (the latter of which can be destroyed by your own shots, for 50 extra points apiece); it is therefore advisable to aim for their claws first (which are each worth 1000 points, when destroyed), before aiming for their noses (which are both worth 2000 points when destroyed). Once you've destroyed all four of those claws and both of their noses, they'll no longer be able to fire any more projectiles (or needles) at you from them so you should then aim for their tails (which are both worth 5000 points when destroyed) before aiming at the centres of their bodies (which are both worth 10000 points when destroyed) to finish them off - they'll then emit a scream of death and explode and you'll also receive 45000 more points once they have done so as the text "DESTROYED THE TARGET!!" appears, on the screen. As with Triple-Eye, you can also aim for one of the two groups of three legs on their sides to defeat them instantly (without having to destroy their claws, noses, tails, or centres of their bodies); however, like him and all subsequent bosses in the game (apart from Danger-Seed himself), they shall retreat if you take too long to defeat them, and the text of "MISSED THE TARGET ENEMY!!" will appear on the screen for a second time (but again, you shan't incur any penalty if this happens). Now it is onto the third stage.

Enemies who appear on Stage 3
BOSS: Roller-Snail (ローラースネイル) - This enormous snail shall attack by firing projectiles from the roller from which he gets his name and megaphylls from the two launchers that are mounted on either side of it (the latter of which can be blocked by your own shots, for 50 extra points apiece); therefore, it is advisable to aim for his head first (which is worth 2000 points when destroyed), then aim it for the roller itself (which is worth 3000 points when destroyed). Once you have destroyed the eponymous roller, he will no longer be able to fire any more projectiles at you from it, so you must then aim for the two launchers that are mounted upon either side of it (which are both worth 10000 points when destroyed), to finish him off - he will then emit a scream of death and explode, and you will also receive 30000 more points once he has done so as the text "DESTROYED THE TARGET!!" appears on the screen. You can also aim for one of the "orbs" on either side of his roller to kill him instantly without having to destroy his head, roller, or launchers; however, like Triple-Eye, both of the Strike-Ants, and all of the subsequent bosses in the game (apart from Danger-Seed himself), he will retreat if you take too long over defeating him and the text "MISSED THE TARGET ENEMY!!" will appear on the screen (once again, you shan't incur any penalty).

Enemies who appear on Stage 4
BOSS: Hunter-Moth (ハンターモス) - This enormous moth shall attack by firing projectiles from his antennae and fibres from his wings (the latter of which can be blocked by your own shots, for 50 extra points apiece); therefore, it is advisable to aim for his antennae first (which are worth 2000 points when destroyed), then aim it for his head (which is worth 10000 points, when destroyed). Once you have destroyed his antennae, he will no longer be able to fire any more projectiles at you so you should then aim for his tail (which is worth 3000 points when destroyed) to finish him off - he'll then emit a scream of death (and explode) and you will receive 30000 more points once he has done so, as that text "DESTROYED THE TARGET!!" appears on the screen. You can also aim for one of his wings to kill him instantly (without destroying his antennae, head, or tail); however, as with Triple-Eye, the Strike-Ants, Roller-Snail and all other subsequent bosses in the game, he will retreat if you take too long over defeating him and the text of "MISSED THE TARGET ENEMY!!" will appear on the screen. Once the screen has faded out you shall receive 50000 points for every ship that survived the first half of this game - along with 20000 points for every special weapon you still have and 10000 points for every bit of energy you still have. Now to the fifth stage.

Enemies who appear on Stage 5
BOSS: Multi-Squid (マルチスクイド) - This enormous squid attacks by firing beams at you from his tentacles and spitting centipedes at you from his mouth, the latter of which can again be blocked by your own shots for 50 extra points apiece; his mouth is also his only vulnerable point, and it can only be attacked while it is opened (i.e. while he is spitting centipedes at you). Once you have fired enough shots into his mouth to defeat him, you will receive 60000 points as he emits a scream of death and explodes - and you will also receive 60000 more points once he has done so as the text "DESTROYED THE TARGET!!" appears on the screen. However, as with Triple-Eye, the Strike-Ants, Roller-Snail, Hunter-Moth and all subsequent bosses in the game (apart from Danger-Seed himself), he will retreat if you take too long over defeating him, and the text "MISSED THE TARGET ENEMY!!" will appear on the screen; if you allow this to happen, then the following stage shall take place on Saturn instead of Jupiter with the boss of Monster-Head (who is a cross between him and Stage 6-J's boss, Shark-Mouth). However, the songs you'll hear from the Yamaha YM-2151 during it will be the same as on 6-J.

Enemies who appear on Stage 6-J
BOSS: Shark-Mouth (シャークマウス) - This enormous shark-style creature attacks by firing bubbles from his left arm and projectiles from his right (the former of which can again be blocked by your own shots for 50 extra points apiece); once again, his mouth is his only vulnerable point, and once you have fired enough shots into it to defeat him, you will receive 60000 points as he emits a scream of death and explodes. You will also receive 70000 more points once he has done so as the text "DESTROYED THE TARGET!!" appears on the screen - however, as with Triple-Eye, the Strike-Ants, Roller-Snail, Hunter-Moth, Multi-Squid, and all subsequent bosses in the game (apart from Danger-Seed himself), he will retreat if you take too long to defeat him and the text "MISSED THE TARGET ENEMY!!" will appear on the screen. If you allow this to happen, the following stage will take place on Pluto instead of Uranus, with the boss of Monster-Mouth (who is a cross between him and Stage 7-U's boss, Twin-Claw); however, the songs you'll hear from that Yamaha YM-2151 are the same as 7-U.

Enemies who appear on Stage 6-S
BOSS: Monster-Head (モンスターヘッド) - This enormous "cross" between Multi-Squid and Shark-Mouth attacks by firing bubbles from his left arm and projectiles from his right, while spitting centipedes from his mouth (the first and third of which can be destroyed by your own shots, for 50 extra points apiece); as with both of those two, his mouth is his only vulnerable point, and once you have fired enough shots into it while it is open to defeat him you will receive 60000 points, as he emits a scream of death and explodes. You will also receive 150000 more points once he's done so, as the text "DESTROYED THE TARGET!!" appears on the screen - however, like Triple-Eye, the Strike-Ants, Roller-Snail, Hunter-Moth, the aforementioned Multi-Squid and Shark-Mouth, and all subsequent bosses in the game (apart from Danger-Seed himself) he'll retreat if you take too long over defeating him and the text "MISSED THE TARGET ENEMY!!" will appear on the screen. If you allow this to happen, the following stage will take place on Neptune instead of Uranus or Pluto with the boss of Ultimate-Tiger (who is a cross between Multi-Squid, Shark-Mouth and Twin-Claw).

Enemies who appear on Stage 7-U
BOSS: Twin-Claw (ツインクロー) - This enormous (but indeterminate) purple creature shall attack by firing lasers from the centre of his body and boomerangs from the two claws that have given him his name (the latter of which can be blocked by your own shots, for 50 extra points apiece); his body is his only vulnerable point, and once you have fired enough shots at him to defeat him, you shall receive 60000 points as he emits his scream of death and explodes. You'll also receive 80000 more points once he has done so as the text "DESTROYED THE TARGET!!" appears upon the screen again - however, like Triple-Eye, the Strike-Ants, Roller-Snail, Hunter-Moth, Multi-Squid, Shark-Mouth and Monster-Head (and Ultimate-Tiger and Monster-Mouth), he will retreat if you take too long over defeating him, and the text "MISSED THE TARGET ENEMY!!" will appear on the screen for what'll be a last time.

Enemies who appear on Stage 7-N
BOSS: Ultimate-Tiger (ウルティメイトタイガー) - This enormous "triple-cross" between Multi-Squid, Shark-Mouth, and Twin-Claw attacks by firing lasers from the centre of his body, bubbles from his left arm, and projectiles from his right arm while spitting centipedes out of his mouth (and the second and fourth of these can get destroyed by your own shots for 50 extra points apiece); as with Multi-Squid and Shark-Mouth, his mouth is his only vulnerable point, and once you have fired enough shots into it while it is open to defeat him, you will receive 60000 points as he emits a scream of death and explodes. You will also receive 300000 more points once he has done so, as the text "DESTROYED THE TARGET!" appears on the screen - however, as with Triple-Eye, the Strike-Ants, Roller-Snail, Hunter-Moth, the aforementioned Multi-Squid Shark-Mouth and Twin-Claw (along with Monster-Mouth), he will retreat if you take too long over defeating him, and the text "MISSED THE TARGET ENEMY!!" will appear on the screen for the final time. No matter how long you may take over defeating Danger-Seed, he will never retreat.

Enemies who appear on Stage 7-P
BOSS: Monster-Mouth (モンスターマウス) - The enormous "cross" between Shark-Mouth and Twin-Claw attacks by firing lasers from the centre of his body, bubbles from his left arm, and projectiles from his right arm (again, the second of which can be blocked by your own shots for 50 extra points apiece); as with Shark-Mouth, his mouth is his only vulnerable point, and once you've fired enough shots into it (to defeat him) you'll receive 60000 points, as he emits a scream of death and explodes. You will also receive 200000 more points once he has done so, as the text "DESTROYED THE TARGET!!" appears on the screen - however, as with Triple-Eye, the Strike-Ants, Roller-Snail, Hunter-Moth, Multi-Squid, the aforementioned Shark-Mouth and the aforementioned Twin-Claw (along with Ultimate-Tiger), he'll retreat if you take too long to defeat him and the text "MISSED THE TARGET ENEMY!!" will appear on the screen for a final time. Now it is onto the eighth & final stage, which has a total of five boss battles.

Enemies who appear on Stage 8
BOSS: Danger-Seed (デインジャーシード) - Before you have to fight the final boss of this game, you have to fight Triple-Eye, the Strike-Ants, Roller-Snail, and Hunter-Moth again (who are all coloured differently and move much faster than before); he will attack by trying to stay ahead of your ship, and spitting pink rings of electricity from his head at you (which can be blocked by your own shots for 50 extra points apiece but will explode into four smaller rings of electricity once you have done so). Therefore, it's advisable to aim for those four quarters of his shell first to expose his innards before proceeding to aim for his legs - and once you have destroyed his legs, he shall start following you around the screen. Once you have fired enough shots at him to defeat him, you will receive 500000 points as he emits a scream of death and explodes; unlike all the previous bosses in the game, he'll never retreat no matter how long you take over defeating him. Your ship will then fly directly to the end of the stage, as the text "EMERGENT ESCAPE!" appears on the screen - and you'll now receive 10000 points for every bit of energy you have remaining then receive a 1000000-point bonus as the text "YOU ARE PRAISED FOR YOUR COMPLETED MISSION." appears on the screen. Once the screen has faded out, you can sit back and enjoy the ending, which shows Danger-Seed's pod exploding and the large Combined Ship (regardless of whether you were controlling it for the last four stages or not) flying back to Earth, as the game's credits roll underneath it, then landing in Japan (which is probably the reason why the game was never released in the United States); the screen shall then fade out to a Buddha-like alien with the text "BUT, PEACE IS NOT ALWAYS KEPT LONG. TO BE CONTINUED..." underneath him. Despite those last three words, the game never begat a sequel.