You play as Diaz, a genetically modified being created by aliens to assist in their mad plot to take over the world. You quickly learn the horror of your misdeeds and seek to bring down this alien organization from the inside, saving the world in the pro—
Oh, wait, that's not right.
No, it turns out that you're not Diaz at all. You're actually Johnny Slater, Secret Service agent extraordinaire, kidnapped by aliens and disguised as Diaz to prevent the evil alien menace from making a clone of the President and using him to take over the world.
...the story isn't the most original thing in the world. What is original about the game is its unique combat system. When engaging in a fight with an enemy, you and your opponent immediately put up your dukes and begin circling around each other. You navigate a series of menus to determine if you want to punch, kick, or throw the enemy, and then you go on to specify exactly what kind of punch, kick, or throw you want to use. It's a rather interesting blend of an RPG/Fighting/Wrestling game. Additionally, while your character does level up in a traditional RPG style, he also levels up in several other ways. The various moves that you use also level up to increase their power, and all of the limbs that your character uses in combat level up their offense or defense depending on how often you use them/how often they get hit.
Despite this interesting system for combat, it's very easy to recognize that the game is quite flawed. Outside of combat, the character can be rather difficult to control, and most of the game consists of little more than running down dozens of similar-looking hallways, blowing up robots, and occasionally fighting a new enemy. But it's entertaining. There are few other games, after all, where suplexing a horrific monster isn't just one way to take it out- it's the best way to take it out.
The game was released to rather average reviews and scores, and would probably have completely disappeared from peoples' memories were it not for the fact that it is one of only a handful of RPGs released for the N64.
This game contains examples of:
- Artificial Stupidity: Given that most of the enemies follow their routines to a fault, some of them may become suicidally obsessed with doing something that leaves them wide open, and will keep doing it until they succeed. The worst example is the foes who just suddenly decide that they must grapple with you, and won't stop trying no matter how many times you shatter their kneecaps and send them flying.
- Boss in Mook Clothing: Gacrux. Dear God, Gacrux. The game recognizes it as a normal enemy, but many people have less trouble with some bosses - up to and including the final boss - than they do with this monster. It has excellent stats, a breath weapon (meaning you have to spend the entire fight standing right next to it to keep it from using said weapon), and can charge up his attacks at full speed while he's running. Last but not least, its bladed arms are all but impossible to block, and he's one of the few enemies that can use them to launch combo attacks! Luckily, it rarely appears and can usually be avoided when it does, but if you're playing the game's bonus survival mode... hope you got some good items beforehand.
- Bullfight Boss: The final phase of the fight with two gigantic monsters involves the red monster charging straight at you once the white monster is dead. You have to stand in front of a weak wall and run out of the way just in time, allowing the monster to burst through the wall and fall to its death in the Bottomless Pit beyond. And yes, it is possible to be a little too late and get tackled by the monster to your own death, and yes, the timing to not die alongside it is very, very tight.
- Crosshair Aware: One of the two boss fights that do not utilize the typical combat system has a crosshair following you, telling you where a giant monster's fireballs are going to land. You need to get the crosshair to target the other giant monster.
- Dual Boss: A boss fight that does not involve the game's normal combat system has you fighting two enormous monsters at once. Well, not so much 'fighting' them as running away from them and using trickery (specifically, the two aforementioned tropes) to beat them both.
- Escape Sequence: The entirety of the second level of the game consists of you running away from an enormous monster. And it's the kind of escape sequence where, every time you think you've gotten away from it, the monster returns by coming through a secret door or coming down an elevator.
- Everything Fades: All defeated enemies turn white before disintegrating (aside from the robotic ones, which still explode into pieces that disappear). Unusually for this trope, you get to see this happen in cutscenes multiple times prior to your first battle, so it's apparently a common trait to all Hybrids.
- Evolving Attack: Part of the RPG mechanics of this game is this, with you gaining more attacks both from leveling up your body parts and receiving attacks you don't have from enemies. It even works with the secret "Combo Attacks"... if you can figure out how to do them.
- Exponential Potential: By the end of the game, depending on how many moves you learned from enemies, you might have around 70 different moves at your disposal, spread amongst punches, kicks, and wrestling moves. It is extremely unlikely that you will be using all of them evenly in combat.
- Giant Space Flea from Nowhere: The evil alien traitor was really being secretly mind-controlled the whole time by an entity that identifies itself as a parasitic organism. Bonus points for somewhat resembling an actual flea.
- Gratuitous Japanese: Attacks directed at opponents on the ground are called "Newaza", which is an untranslated Japanese term from Judo for techniques performed on grounded opponents, like pins and holds. However Newaza techniques in Hybrid Heaven also include applying your boot to you opponent's head and curb-stomping them, which would not be considered legal ne-waza techiques in actual Judo.
- Harder Than Hard: The 'Ultimate' difficulty. Outside of combat, everything that deals damage to you deals FOUR TIMES AS MUCH of it as it did on Normal (and worth noting; on Hard, that damage multiplier was only 1.5x), to the point where you simply will not have enough HP to survive certain hazards no matter what (hint: fire bad). And you don't fare much better inside combat, as even the first enemy can now kill you in two or three solid hits.
- Heroic Sacrifice: Johnny tackles Diaz off the elevator in order to keep the President safe while there are explosions all around them. Quickly becomes averted as after the battle, the President comes back to save Johnny, and they both escape in time.
- Mirror Boss: The final boss fight of the game is against Diaz, the character you took the identity of at the beginning. During the fight, you'll find that his fighting style is very similar to yours.
- No Cure for Evil: Averted. Some enemies will use healing items to restore their HP.
- One-Hit Kill: There is a rare item you can collect in the game called the Ring Eraser. When you use it in combat against a non-boss enemy, it instantly ends the fight by causing your enemy to fade out of existence. You forfeit the ability to gain EXP or items from beating foes with it, but it can still be a handy panic button in the right circumstances.
- Our Presidents Are Different: Several varieties, all technically personified within the same person. The most obvious is President Target, as you spend a good chunk of the game rescuing the kidnapped President repeatedly from his Hybrid captors. The second is the President Evil form, as the Hybrids' master plan revolves around cloning the kidnapped president and using the clone to take over the world. The final form is President Action, as he does attack the Master at one point to rescue you from one of his psionic attacks, and lands a solid hit in the process, and one of the final moments of the game is the President of the United States running up on a stage and punching out his clone in front of the entire nation before giving a thumbs-up to the protagonist.
- Additionally, if you use a secret code made available by beating the game on Ultimate, you can play AS President Weller from start to finish, seating him (well, the one you're playing as) firmly in President Action territory.
- Percent Damage Attack: Inverted into Percent Healing Item; all of your healing items either heal a set amount of HP, or a set fraction of your HP if you'd heal more HP that way.
- Power Copying: You learn new moves by having enemies perform them on you. It's not a guaranteed chance, and you can't learn a few enemy-only moves that the human body couldn't possibly do. Hope the RNG is kind when it comes to learning the deadlier moves.
- Respawning Enemies: To a point. There are teleporters on the ground of many rooms that spawn enemies if there's not one inside already, but they'll stop working after you've killed enough enemies in that room.
- Rule of Cool: Fighting aliens isn't anything new, but fighting them with punches, kicks, and wrestling moves while they fight back the same way? Win.
- Sequential Boss: And how! The final sequence of the game has you fight a whopping six boss fights in a row with no opportunity between fights to save or heal. Three of the bosses are technically different forms of one enemy, and the other three are all individual enemies. Hope you saved up your healing items.
- Stellar Name: Every single enemy in the game (with the exception of the human hybrids and the Master) is named after a star.
- Subsystem Damage: In combat, individual body parts can be damaged on both you and the enemy. A damaged body part cannot be used in combat until the damage wears off, and certain body parts result in status effects if damaged - If the legs are damaged, then movement is slowed. More dangerously, if the head is damaged, then the character is considered to be unconscious and can do little more than sit back and let the opponent beat the somewhat-living crap out of it until the damage wears off, or they finish the job.
- Suddenly Voiced: Throughout the entire game, the protagonist does not say a single word, and it seems like he is your standard Heroic Mime. Then, during the ending cinematic, he suddenly starts talking (with full voice acting!) as if he'd been doing it the entire time. It's actually pretty jarring.
- Take Over the World: Played horrifyingly straight. No reason is ever given for why the villains want to take over the world. They just do.
- "The Reason You Suck" Speech: The Hybrids have this in spades. Not only are they all amazingly over-confident in their invasion plans of taking over the world (except for perhaps Anna, the most loving Hybrid, and Diaz, who doesn't really care about the invasion and simply wants to kill Johnny), but they all always and continuously complain about how the human race is so inferior to them, and their only apparant reason for wanting to take over the Earth is because they think they're better than everyone else. Not only that, but each of the leaders keep continue telling Johnny that he is fighting for worthless humans, and that he should be dead. Also, it seems that no matter how much ass Johnny kicks, how much of the plan is ruined because of him, and just how much they underestimated him, the Hybrids continually shrug this off and when the leaders fight Johnny themselves, they still think they'll win and be able to go on with their invasion (which by this point is obviously SNAFU), and even when the invasion is completely and totally beyond FUBAR, The Dragon says everything is going as planned. When it comes to over-confident villians who don't even take a hint when their main enemy has single-handedly destroyed their base, ruined their invasion, saved the president, and aborted their whole friggin' species, the Hybrids play this very straight.
- Unexpected Gameplay Change: Two mandatory boss fights don't use the game's typical fighting system. One is a fight against a much bigger version of one of the robotic mooks that requires copious use of your EMP pistol as you dodge its many guns and missile attacks. The other involves the giant monster from the second stage getting a buddy; you are no more capable of hurting them yourself than you were before, and it's thus less of a 'fight' and more a puzzle where your goal is to find a way to use the environment and the bosses themselves to do the dirty work for you.
- Use Your Head: One of the most powerful grappling moves is the good ol' Headbutt - it uses barely any stamina, can fairly reliably render any enemy you can grab unconscious, and it hits twice. For about the damage of any other throw for each hit. There is, however, a rather problematic issue with the move - to learn it, you have to survive it, as well as hope that both the RNG considers the copying a success, and that your teacher doesn't stomp what's left of your face into the ground afterward.
- Wrestler in All of Us: Yes, one of your primary methods of attacking your alien enemies is by wrestling them. While some of these moves are simple suplex and chokehold moves, there are many more that would have absolutely no place in real combat, and oddly enough, seem to actually require the cooperation of the opponent to carry out (like real Professional Wrestling, oddly enough).