''Clash at Demonhead'' (called ''Dengeki Big Bang!'' in Japan) is an open-ended ActionAdventure game developed and published by Creator/VicTokai for the UsefulNotes/NintendoEntertainmentSystem.
You take on the role of a soldier named Billy "Big Bang" Blitz, who is contacted during a vacation with his girlfriend Mary about a kidnapping attempt on Professor Plum, a scientist who constructed a DoomsdayDevice that will [[TheEndOfTheWorldAsWeKnowIt destroy the world]]. At the start of his mission, Bang encounters the kidnapper, a rogue named Tom Guycot. Guycot tells him that he and the seven governors of Demonhead Mountain have taken the medallions used to power the device, and issues a challenge to Bang to try and find them. With no choice but to cut his vacation short, Bang goes off to find the professor and prevent the world from being destroyed...
This game was the inspiration for the name of one of the bands in the ''Comicbook/ScottPilgrim'' comic series, which creator Bryan Lee O'Malley claims was the first NES game he ever had.
! Tropes used in this game:
** If you run out of Shop Calls, you can go to the "WELCOME" sign at the edge of the water on Route 5, where there'll always be a shop available waiting for you.
** And even though the shop's stock rotates depending on how many times you visit it, you'll always be able to buy Microrecorders so that you can have a PasswordSave handy when you need it.
* BatmanGambit: [[spoiler: The Demon possesses your "ally" Michael and uses him to trick you into releasing him.]]
* BullfightBoss: Gazh. His main attack is to dash back and forth along the ground, giving you a clear shot at him if you jump over him.
* BodyguardBabes: Mush, boss of Route 16, has a pair that you have to fight before he appears.
* DeflectorShield: The Barrier item creates a force field around Bang that blocks enemy bullets.
* DestructibleProjectiles: You can shoot down regular enemy bullets with your weapon.
* FairyCompanion: Faysha.
* GiantSpaceFleaFromNowhere: The Demon itself has ''nothing'' to do with Guycot or the DoomsdayDevice. Interestingly, it shows up at the middle of the game, and nobody, good or bad, [[OutsideContextProblem saw that coming.]]
* GuideDangIt: There's no way to know where to find Shark...to find him, you have to [[spoiler:push against the bottom of an otherwise unremarkable all-water route to find the boss room]].
* HopelessBossFight: The Demon [[spoiler:the first time you see him, where every attack he uses on you is an automatic OneHitKill. You're required to lose to him the first time you meet in order to advance the story, and can't harm him without using the Sword of Apollo]].
* InvincibilityPowerUp: The Force ability Karate Power makes Bang impervious to all damage for 30 seconds, and allows him to take down most non-boss enemies in just one or two hits. The only downside is that he can't use his gun while this power is active.
* ItsAWonderfulFailure: [[spoiler:Failing to defuse the bomb causes an explosion, and then you go to the "THE END" screen... but because the bomb went off, you'll notice Bang and company are missing.]]
* JetPack: One of the power-ups you obtain from the shop allows you to fly.
* LavaIsBoilingKoolAid: A Supersuit is mandatory to even go anywhere near it. Without one, you die the instant you make contact.
* LoneWolfBoss: Rowdy, the monster guarding the Hermit. He isn't affiliated with the Demon or his minions, and doesn't even get the standard "boss" music.
* LuckBasedMission: [[spoiler:Disarming the bomb. You have six tries to correctly place all of the medallions, and the MagicCountdown speeds up every time you fail to get them right. Compounding matters, the combinations are randomly generated with each game, and you're never given any clues as to what medallion is supposed to go where.]]
* MeaningfulName: Guycot is a pun for the Japanese word for "skeleton".
* MonsterIsAMommy: [[spoiler: After you defeat the Demon, you stumble upon a room full of his/her/its eggs, which you have to destroy before you can escape its lair.]]
* NonLethalBottomlessPits: While falling into pits doesn't kill you, you get taken to an area where you have to fight your way back to the surface, making you start the route over again.
* OxygenMeter: The timer for the Aqualung acts as one. Once it runs out, you lose one point of health for every second you're underwater.
* PainfullySlowProjectile: Enemy bullets fly much slower than yours do, and thus can be shot out of mid-air.
* PasswordSlotMachine: [[spoiler:The bomb disarmament sequence. Correct guesses are "locked in", and you have to figure out where the rest go on your own.]]
* PlotCoupon: The medallions.
* PowerFloats: Acquiring the "Levitation" power-up allows Bang to float around in the air for a short time.
* RecursiveReality: At the end of the game Bang expresses his desire to have a video game made of his adventure.
* SizeShifter: Max, the Governor of Route 7, starts out as a tiny runt of a boss, but as you damage him, he increases in size until he's big enough to float around and start firing smaller versions of himself at you.
* SkippableBoss: [[spoiler:Pandar]].
* SoundtrackDissonance: The same triumphant music that plays during the ending also plays [[spoiler: during the Bad Ending where the Doomsday Bomb explodes and, presumably, everyone dies.]]
* SpreadShot: The Big Shot/Thundershot weapon fires a powerful spread of projectiles, but has limited ammunition.
* SprintShoes: The Power Boots boost your running speed for a short time.
* SwordOfPlotAdvancement: The Sword of Apollo.
* ThreateningShark / FishPeople: The appropriately-named Shark, who lords over Route 22. The battle takes place underwater, so you'll need an Aqua Lung to survive.
* TheUnfought: [[spoiler: Tom Guycot. He attacks you at the very beginning of the game, but after you get tricked into releasing the Demon, the Demon curbstomps him offscreen and steals his medallion afterward.]]
* VillainsNeverLie: Subverted. Guycot lied about [[spoiler:the number of medallions...there are really only six. Pandar, one of the Governors, doesn't carry one. Guycot had his medallion stolen from him by the Demon.]]
* WarmUpBoss: Gazh, the boss of Route 11, is usually the first one players fight, and he has a very predictable fight pattern (dash back and forth, get shot, shoot a line of fireballs, rinse, repeat).
* WeaponizedHeadgear: Mush likes to toss his mushroom-shaped cap at you.
* WeSellEverything: The shop sells every item you can use in the game, but its stock rotates depending on when you visit. After your 30th visit to the shop, all of the items are available for sale at half price for that visit only.
* WingedSoulFliesOffAtDeath: What happens after you bite the dust.