Nitrome is an independent game developer known for its Flash games, many of which are on Miniclip. Nitrome's games often have highly unusual gameplay that forces the player to think well outside the box.
Absurdly High-Stakes Game: "Flipside" is a fun racing game... that determines whether the protagonist stays in prison or not.
Advancing Boss of Doom: Present in both "Ribbit" (as a hybrid of a rhinoceros and a beetle) and "Off the Rails" (as a train.) The final level of the latter has two such bosses, one in front of you and one behind, preventing you from going too fast or too slow unless you do a jump and manage to get over it, in which case you can reach the level's end quickly and without impediment.
Advancing Wall of Doom: "Avalanche" has a straight one. "Cave Chaos" uses an odd variant: the scenery constantly assembles in front of you and disassembles behind you, forcing you to keep up or fall to your doom. "Super Treadmill" takes place on a treadmill, and you lose if you fall off either side.
Bad Boss: The Big Bad of "Office Trap". He forces prospective employees to make their way through an office building riddled with death traps and agrees to give a temporary work contract to all the survivors.
Be Yourself: By Day 17 of "Super Treadmill", Billy no longer cares about his weight or the competition, and if he decides to lose it, he'd rather eat healthy and exercise than use the Super Treadmill. Of course, his Uncle Rico is hell-bent on making Billy lose weight on the treadmill...
Black Knight: The protagonist of "Tiny Castle", at least in terms of how he dresses.
Black Sheep Hit: One of their most popular games is "Mutiny", which is a lot simpler in gameplay to most Nitrome games; although it looks like a Nitrome game in terms of design, it's one of their few games with no Bizarre Puzzle Game elements.
Bloodless Carnage: So far, only "Graveyard Shift" and "Parasite" have used blood at all, and in those it's been greenish gunk. "Nitrome Must Die" also uses blood, and its color varies depending on the enemy.
Well, there's a bit of normal, red blood in the vampire level of Pixel Pop.
Death Is a Slap on the Wrist: "Fault Line". You're merely sent back to the last checkpoint you accessed, and any fastened fault nodes that hid it are unfastened.
Deliberately Monochrome: Each level of "Yin Yang" is essentially two in one: one that's on a white background, with everything in black, and one that's on a black background, with everything in white. Everything that's empty air in one world is a solid block in the other. The two main characters can't directly interact, but can sometimes move crates around to open up holes in the other character's landscape.
Dem Bones: Seen in "Small Fry", "Mutiny", and "Numbskull".
Difficulty Spike: Practically their Signature Style. The first five to eight levels will be pretty easy tutorial levels, but then things get crazy. Averted by some games, though, like Tiny Castle (it's just one level) and Blast RPG (the level system is a bit different).
Fake Difficulty: Nitrome's specialty is to take things that would usually be considered such, particularly Interface Screws, and try to make them reasonable and enjoyable limitations.
Follow the Leader: Many Nitrome games can be traced to an individual game they're copying (for instance, "Small Fry" is a mimic of Lemmings.) To its credit, it's often quite inventive in creating new challenges within the same basic framework.
The game sequels also tend to be exactly like additional levels of the original games. Notable exceptions include "Test Subject Arena" and "Skywire VIP", although there were individual sequels to "Skywire VIP" that fit their normal sequel formula.
Foreshadowing: In the background of Nitrome Must Die, there's a whiteboard labeled 'New game ideas'. One of the ideas was a 'Game with blobs'. A month or two later, Swindler was released, in which the protagonist is a green blob.
Going Commando: Judging by the intro of "Toxic 2", the protagonist isn't wearing anything under that radiation suit.
Goomba Stomp: Your alternate attack in "Frost Bite." "Ribbit" is an interesting variation in that you can only do this if you've charged up for a high jump — standard jumps just result in Collision Damage.
Grappling-Hook Pistol: Your way of getting up the mountain in "Frost Bite," as well as your primary weapon.
Gravity Screw: "Rush" has as its gimmick the ability to flip your character from floor to ceiling, not unlike VVVVVV. You can also flip your opponents' tracks, causing them to get screwed over as well!
"Swindler" is based around being able to rotate rooms/levels.
Have a Nice Death: It's worthwhile to lose intentionally in "Mutiny" just to see the unique messages for every battle.
He Knows About Timed Hits: Usually, the necessary information is on signposts scattered around the level. "Cheese Dreams" gives these from the main character's perspective, with the inevitable lampshading of "Why are my thoughts appearing on these signs?"
Hourglass Plot: The ending of Super Treadmill shows Billy having finally lost weight, while Uncle Rico becomes obese.
100% Completion: There's a fuse in each level of "Rustyard," and several vials of acid in each level of "Toxic 2." In each case, you're encouraged to collect them all, though neither explains whether anything special happens if you do (a screen in the former says "Have you been collecting those fuses? What for?"). Of note is that these are among the few Nitrome games that have no leaderboard for Scoring Points or completing a level in the smallest possible time.
Husky Russkie: One of the protagonists of "Rubble Trouble." He has a tendency to provide powerful explosives with only vague explanations of where he got them.
Interface Screw: "Super Treadmill" and supposedly its Spiritual Sequels are based on old NES games, so Nitrome has put in occasional TV static and glitches into AV mode.
Invisible Monsters: The levitating swords in "Tiny Castle" aren't actually levitating — they're held by invisible swordsmen, who flash when struck.
Just Toying with Them: Your Sarcastic Devotee in "Toxic 2" is certain the robot leader is doing this — you can't possibly have gotten this far without her wanting you to. It's never entirely clear whether he's right about this, though either way, a good player is being underestimated.
In "Headcase," it teleports the main character to "a world where everyone walked on walls" and turns him into a superhero.
Luckily My Shield Will Protect Me: How you prevent zombie goop from killing you in "Graveyard Shift". Pieces break off it as it blocks more and more hits, but it never completely breaks, and you can replace it at some points.
Ludicrous Gibs: "Graveyard Shift" and "Parasite" are straight examples. "Off the Rails" has gore, but no blood, with dead bodies splitting into neatly sliced bits resembling steaks. "Final Ninja" has no blood or gore, just body parts flying every which way in a disturbingfashion.
Minimalism: Gunbrick, J-J-Jump, Turnament, and Ice Beak. So much so, they are the size of the game thumbnails!
Mix-and-Match Critters: The Mooks in "Ribbit" are standard versions of this, like a snake with porcupine quills. The title character is a variant, with a rabbit's head and a frog's head joined by their necks, lacking a torso or limbs. (Note that Ribbit is not a Multiple Head Case or Two Beings, One Body, referring to itself as "I.")
Money Spider: Lampshaded in "Tiny Castle" at the end—the princess has so much money that she feeds it to the monsters.
Powered Armor: The protagonist of "Final Ninja" wears some, though it's not quite as powerful as most fictional examples, being more focused on stealth.
Precision F-Strike: Nitrome is notable for their games generally not having any profanity, though the opening and ending of "Nitrome Must Die" had Austin and Justin's chat screens peppered with Symbol Swearing, and the word "damn" is used early on in "Super Stock Take".
The Power of Love: Twisted in "Parasite." Certain areas are covered in "happy gas," somehow related to an overwhelming force of positive feeling. The title character is unharmed for gameplay purposes, though he strongly dislikes the feeling. His mind-controlled minions explode.
Reality Warper: The protagonist of "Fault Line" can fold the 2D levels in on themselves, causing everything in the folded area to temporarily vanish from existence—for instance, he can bypass walls by folding the space around the walls and leaving empty air behind.
Running Gag: Ever since "Cheese Dreams", every time the creators have shown a moon, it's been made of cheese.
Scavenger World: This is the entire point of "Steamlands". It's imperative to steal your enemies' tank parts after your destroy their engine room.
Screen Tap: In "Test Subject Blue", the scientist occasionally taps on the window in the test chamber.
In "Test Subject Complete," one of Dr. Nastidious's soldiers takes it a bit farther and pounds the glass with his fist.
Secret Level: Several in "Toxic 2", accessed through blue teleporters in out-of-the-way areas.
Segmented Serpent: One of the nastier enemies in "Graveyard Shift", and the final boss in "Aquanauts". Naturally, you kill them bit by bit.
The ones in "Bullethead" can take relatively few shots, but are only hurt when shot in the tail. They move left-to-right and right-to-left, descending a little with each pass, and are long enough that you only have a small opening to shoot the tail before another part moves in front of it.
Sugar Apocalypse: The technology-free garden world on which "Parasite" is set is full of cartoonishly happy animals and benevolent nature spirits. The titular parasite kills the animals, harvests the spirits, and turns the entire world into a barren waste.
Unexpected Gameplay Change: We have "Test Subject Blue", which plays out like Mega Man meeting Portal, then "Test Subject Green", where it's still the same formula, but not long after that we get "Test Subject Arena", where instead of getting a food pill, the blue and green enzyme fight with proton/enzyme blasts.
There's a similar example in the "Skywire" series. The first sequel, "Skywire 2", is simply a bunch of additional levels to the original. "Skywire VIP", however, has you guessing who all the people you've been riding around are supposed to be.
There's also "Mega Mash", which is a gameplay roulette of seven different sub-games with an overall puzzle element. The premise is that you're playing a broken Nitrome Enjoyment System cartridge which is constantly glitching out.
Up to Eleven: Nitrome takes their small retraux games to new heights with Gunbrick. The entire game is played in the tiny 50p x 50p icon! They have a full screen option so you don't scream in pain from the eyestrain, thankfully.
Verbal Tic: Ribbit, Ribbit in "Ribbit" constantly says "ribbit", ribbit.
Villain Protagonist: "Parasite" is about as clear-cut as you can get — you destroy entire planets both for survival and because it's fun. "Worm Food" is another staring example. A few other games, like "Castle Corp", have protagonists who're Anti Heroes.
"Droplets" has a bizarre twist example. The bunnies you've been carefully stop from dying are an evil invading army.
Austin Carter and Justin Bennet from "Nitrome Must Die".
In Cave Chaos 2, worm-like enemies crawl into the protagonist's ear to reshape him into something halfway between his normal self and the standard enemies in the first game. (It's even more disgusting than it sounds.) This forces him to constantly move forward, just like those enemies, although he can still turn around. It also changes the level-complete animation—instead of dancing around happily, he'll stand in one place for a moment, then suddenly start vomiting (apparently purging the worm, since he's back to normal in the next level.)
Waddling Head: The vikings in the "Ice Breaker" series are a non-enemy example.
Wall Crawl: The protagonist of "Glassworks", due to the special gloves he wears.
Weird Sun: The sun in "Ribbit" has bulging eyes, a slightly downturned mouth, and clenched teeth, and appears to be in significant pain. This is never explained.
You Have Researched Breathing: In Nitrome Must Die, the Bullethead weapon is identical in almost every way to the regular pistol... except that it shoots up.
Your Princess Is in Another Castle: "Tiny Castle" is pretty blatant about this—the princess is in a cage hanging by a rope, and several times you reach the cage just in time for the rope to be pulled and for her to get moved to another part of the castle.