Video games attract all kinds of people, from the casual gamer to the hardcore tournament champion
. But a game that provides a satisfying play experience for one may be frustratingly difficult or yawningly easy for another.
Thus, some games adjust their difficulty level behind the scenes to match the player (ignoring the fact people can just adjust difficulty levels).
When this is invoked, it's important to implement a ranking system so the better players can feel special. That way, casual players feel good about beating the game, and veterans still feel challenged trying to get the SSS-level
and beating the True Final Boss
On the other hand, some players inevitably prefer kicking ass on Easy and will get annoyed that the game won't let them, while others would rather play on Hard even if if means repeating That One Boss
20 times and will feel cheated if the game "lets them win." More opportunistic players will quickly learn to intentionally play just well enough to continue but no better
to keep the difficulty down.
This is very similar to Rubber-Band A.I.
. Can cause problems such as Empty Levels
. The opposite of Unstable Equilibrium
, where the game gets harder if the player is doing badly. Not to be confused with Schizophrenic Difficulty
, where the difficulty goes up and down at random, regardless of the player's performance.
When this trope is played in a multiplayer mode, it's Multiplayer Difficulty Spike
, Mercy Mode
, and Difficulty By Acceleration
Video Game Examples:
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Action Adventure Games
- Lego Star Wars II, Indiana Jones, and Batman feature "Adaptive Difficulty" which merely affects the amount of LEGO studs you lose upon death depending on how well you play, which can go up to a very high amount.
- In Cave Story, the Last Cave becomes a much harder level if you enter it with Booster v2.0, whose proficient use is required in the "hidden" version.
- Snatcher had a shooting range which could be accessed for fun. If you get consistently high scores on the shooting range, the game amps up the challenge of the plot relevant shooting set-pieces. It's advised that you do intentionally terrible on the shooting range, or finishing the game may require inhuman reflexes.
Beat Em Ups
- God Hand will adjust the difficulty up a level (1, 2, 3, and Die) if the player lands enough hits on enemies, increasing enemy strength and durability. It will then scale the difficulty back down if they take too many hits. You gain more rewards for defeating more enemies at higher difficulty levels. The game has "normal" difficulty settings, as well - the difficulty level never rises above 2 in Easy Mode, and Hard Mode has you always on Level Die.
- In The Simpsons Arcade Game, the amount of enemies on screen depends on how many people are playing. In the boss fight against Smithers, if there are more than 2 players he won't throw any bombs you can throw back.
- The Teenage Mutant Ninja Turtles: The Arcade Game features a dynamic difficulty involving the enemy count that kicks in depending on several factors, including how many people are playing in the game, and — chiefly in one-player mode — whether or not the player has died/continued. Beating any level without losing a life will make the subsequent level much tougher (in that you have many more enemies to contend with in each wave), and dying at all will reset the soldier count to an easier level. Also, some bosses (namely the Dual Boss with Rocksteady and Bebop, and the final battle with Shredder) will have more health if you reach them without dying.
- In Aces Wild: Manic Brawling Action, your Rank fluctuates as you deal and take damage. A higher Rank makes enemies attack more aggressively, but it also boosts the number of points you score with each hit, and how much "Wild" (energy used for power punches and health-restoring "Panic" attacks) you generate per hit.
- This shows up in Forza Motorsport 4's World Tour. The AI starts ridiculous easy, but the more events you win, the harder they become.
- The Need for Speed Underground series utilizes dynamic difficulty in two ways: first, the more you tune your car, the faster the other cars will be; second, the "Catch Up" feature causes competing cars to go faster as you pass them, and slower as they pass you. In theory, the latter makes the game more balanced; in practice, it's nothing but Fake Difficulty. With regards to the former, one of the recommended strategies if you're having difficulty is to remove all your upgrades, as the lower speed makes it much easier for you to react to obstacles and avoid mistakes. It's like playing in slow-mo.
- Gran Turismo 4 uses "A-Spec Points" to encourage you to choose slower, less powerful cars to win the race: the more powerful your car is, the smaller your score will be. If, for example, you manage to win against a squad of sleek German machines with a puny little Pontiac Sunfire, you'll win 200 points; but if you win the race with the superpowered Polyphony Formula Gran Turismo, you'll win 1 single point.
- Many edutainment games start you off on the lowest difficulty setting by default. Then, depending on how well you're doing, it will start to throw harder challenges at you. If you have trouble on a certain difficulty level, it keeps you on that level.
- In Jump Start Typing, you have to type to a certain level of words-per-minute to unlock Coach Qwerty from the trophy closet, and the activities are merely to practice typing. The difficulty of the game, however, is proportional to how well you do in the initial trial, and it is therefore possible to finish the game in a ridiculous amount of time by simply typing at 1 word per minute so the goals are set low, and then proceed to steamroll through it all.
- Mortal Kombat vs. DC Universe features this type of AI. Lose, and it will edge down the difficulty slightly. Lose more, and it keeps sliding the difficulty down until you can win and continue progressing through the story. The final boss is not exempt from this difficulty edging, either.
- Most of Capcom's fighting games will make it so that the opponent gives more and takes less damage the more you win. This occurs on any difficulty setting.
- SmackDown vs. Raw: After a few wins the computer will kick into overdrive and engage The Computer Is a Cheating Bastard mode to make you lose, no matter how much it has to break the game to do so.
- SiN Episodes: Emergence features the Personal Challenge System, designed to adapt itself to the player's skill level and varies the skill, numbers and toughness of enemies faced in accordance the player's performance. It was claimed that thanks to this, a proficient FPS player and a brand new FPS player would be able to finish the game in roughly the same amount of time. However, a bug present on release in the system caused the game to never ease up on players making it overly challenging and unforgiving. This has since been corrected. note
- Left 4 Dead features a "director AI" that spawns Infected based on how easily the players made it past the previous encounter. If the skirmish ends with the players healthy and having used few ammunition, the director sends in a horde. If the players are dying and low on ammo, the director only sends in a few. If you are playing on Expert and are doing poorly, it says "why aren't you dead yet?" and redoubles its efforts. Whimper.
- Killing Floor, in addition to the regular difficulty levels, increases the number of specimens per wave and gives them more health depending on the number of players.
- Many checkpoint-based shooters give you a number of checkpoints/savepoints inversely proportional to your skill level and how far you progress in a level without dying.
- The Expansion Pack to Galactic Civilizations II can be set to feature massive events that intentionally destabilize the playing field from time to time to keep things interesting. Additionally, the player can also tweak the personality, competence, and starting alignment of the factions.
Light Gun Games
- The arcade Lethal Enforcers started with a certain amount of time a baddie took to hit you (a bit under three seconds). This gradually decreased over time and reset only after you took a hit. The upshot was that you'd have to shovel in a ton of tokens to get to the end of the game no matter how good you were. Lethal Enforcers 2 was even more brutal, with a shorter starting time and a much faster decrease.
- Many Light Gun Games amp up the difficulty if there are two players present. Which means if some little kid decides to jump in on your game despite your protests, the game becomes much harder because the presence of an annoying kid who doesn't know how to play has made enemies more numerous and difficult to destroy.
- For a specific example: The House of the Dead III. With 2 players playing, zombies double in number, and bosses take twice as much shots to cancel their Break Meters. This is especially bad with The Fool's swiping attack, which requires 6 shots in less than 2 seconds to cancel, and that's only in 1-player mode. In 2-player mode, you need 12 shots (6 per player), so unless the other person is competent at the game, he or she will be bogging you down and making you lose a life EVERY TIME, NO MATTER WHAT. Also, for the whole series: Playing good or poorly in a stage will change the boss' speed.
- Brave Firefighters, though not exactly a "true" gun game (you use simulated firehoses instead of guns), operates on a similar principle. If you play in 2-player mode, the time bonuses for clearing segments quickly are lower.
- EVE Online features wormholes, where the amount of enemies depends on the number and size of the player ships. Don't ever try to bring a carrier (a capital ship) into the fight, however. Each time you do, there is an extra spawn of a few sleeper battleships. Unless you are doing this specifically to farm them, this is tantamount to suicide.
- A staple of open-world content in Guild Wars 2. Dynamic events adjust the number of enemies, variety of abilities available to bosses, and HP of destructible objects according to the number of active players present.
- Most games developed by Platine Dispositif feature a "Phase" system, where higher phase levels increase the number and speed of bullets the enemies shoot at you. Getting hit or using bombs decreases your phase level, while defeating mini-bosses (or bosses) increases it. Demonic Mode, which is Harder Than Hard, starts you off at the highest phase level, and it never decreases.
- Games in the Crash Bandicoot series will often disable environmental hazards and/or move checkpoints if a player dies too often on one particular obstacle.
- The spin-off party game Crash Bash does this for practically every game with computer-controlled opponents. If you win too easily on the first match, the computer suddenly gets harder for the second, and vice versa if you lose by a lot of points. Case in point: the final boss (a PONG clone) is nearly untouchable the first time you fight him, but every time you lose, he gets easier and easier until he can't even return the very first ball. However, the instant you DO score against him, his difficulty goes back up. Winning this fight means using his Dynamic Difficulty to make sure he's easy enough at the first ball that you can still win when he hardens after being scored against.
- Ratchet & Clank has a leveling system, and experience points are kept when you die. If you die a lot, you will end up getting stronger than if you played through the game without dying or revisiting old areas. In addition, dying against a single obstacle too many times will either disable it or have the checkpoint moved.
- The Mega Man Zero series assigns you a rank after every mission based on how well you completed it. If you fought a boss while having an A or S rank, the boss used new, stronger attacks which Zero would gain for himself after winning the battle.
- The Spyro the Dragon series scales difficulty depending on the skill of the player. Unfortunately, this results in an individual playing on the lowest difficulty setting being incapable of completing the third game 100%.
- Perhaps the earliest advertised use of this is in Gods, which would at predetermined points give the player a "help bonus" if he was doing poorly, or spawn additional enemies if he was unhurt.
- In Master Mode of Tetris The Grand Master 2 and 3, certain game mechanics behave this way:
- TGM2 requires the player to clear each section in under 65 seconds to get a Master or Grandmaster grade (the latter being the ultimate goal of the game), and failure to do so in any section caps the player's grade at S9 for the session. However, clearing sections in 63 seconds or less can raise the bar for subsequent sections for that session. The time limit for section 6 is 65 seconds or the average time for the first 5 sections plus 2 seconds, whichever is lower, and the time limit for each subsequent section is 65 seconds or the previous section time plus 2 seconds, whichever is lower.
- In TGM3, if you complete a section fast enough, you will get a "COOL!" message, which gives a bonus to your grade. Each time you do this, it also causes the speed level to increase by 100. Meaning, if you get a COOL!, then advance to level 200, the game will act as if you're at level 300. Do this for the first two sections and you'll hit maximum drop speed at only three-tenths into the game (as opposed to halfway through if you don't get any COOL!s). In addition, the time limits to get a COOL! are also set as "X seconds or 2 seconds more than the previous section's time", with lower values of X for later sections.
Real Time Strategy
- The Homeworld series scales enemy fleets to match yours, to a certain extent. In the first game, it's easy to have an overwhelmingly powerful fleet anyway by abusing the Cap system by capturing enemy ships. In Homeworld 2, capturing ships is no longer practical and enemy fleets scale so heavily in comparison to yours that building more ships makes the game harder, not easier. Amusingly, a well-known exploit is to retire your fleet at the end of a mission — the next one will be staggeringly easy as you can rebuild your fleet in a few scant minutes.
- The Binding of Isaac does a variation on this. While playing through the game more and more times unlocks more items to use, it also inevitably unlocks more bosses to have to fight (including stronger versions of previous bosses) and more levels to have to clear, making the game harder and longer the more you play it and beat it. One achievement even blatantly makes the game harder (increasing the likelihood of champion enemies and curses,) and beating Isaac in the Cathedral for the first time increases the likelihood of a curse even further.
- The Battle Tower in Pokémon becomes harder the better you are. However, rather than just increasing AI skill, it also stacks the opponent's teams against you and manipulates the RNG.
- Jossed by RNG-researching hackers, who have disproven claims of AI manipulation and suggest Artistic License - Statistics is to blame. The same complaints are also false for spiritual successors the Battle Subway and Battle Maison.
- Pokémon Yellow is a subtle example. You start with a Pikachu (Electric-type), and your rival starts with an Eevee. What he evolves it into depends on whether you win the first two battles with him:
- If you win both battles, he evolves it into Jolteon, which is resistant to Electricity.
- If you win one battle and lose or forfeit the other, he evolves it into Flareon, which takes normal damage from Electricity.
- If you lose or forfeit both battles, he evolves it into Vaporeon, which is weak to Electricity.
- The difficulty of a level in NetHack is based on the average of your character level and the dungeon level.
- Final Fantasy VIII: Monster levels depend on the average level of your party, and their attack patterns will differ depending upon their level. As a result, grinding early on without paying any attention to your junctions can and will screw you over utterly.
- Unfortunately some of the bosses (especially the optional ones) would become disproportionately harder as the player gained levels. Some would gain tens of thousands of extra HP for every player level whilst the player's ability to do damage increased by nowhere near that much. This made a lot of the game much easier if the player went for a Low Level Run. It also effectively meant Empty Levels.
- Final Fantasy: The 4 Heroes of Light: Once you open up the Very Definitely Final Dungeon, monsters and bosses will keep pace with the party's levels.
- Fallout 3 assigns experience points based on the difficulty setting. Conversely, the higher your level, the tougher your enemies will be when entering new areas. Fallout: New Vegas also has level scaling for certain enemies, especially in the DLC's.
- SaGa Frontier: Improving your party's effectiveness via Stat Grinding increases the difficulty of enemy encounters.
- In Iter Vehemens Ad Necem, monsters get more difficult as you become more powerful (and boss monsters will appear at particular thresholds), but your companions are not included in this calculation. One easy(-ish) way to win is to collect powerful allies and pets, and have them do all the work for you.
- Guitar Hero 5 has a battle mode called "Momentum", which increases the difficulty every 20 combo (starting at medium), and drops you back down after 3 misses in a row. Warriors of Rock adds "Momentum+", where it increases every 10 combo instead, and automatically drops the leading player back down to beginner difficulty if Star Power is deployed.
- ''DJMAX Portable'' increases the current scroll speed as the player's Fever (score multiplier) goes higher.
- Featured in Rocksmith.
- beatmania IIDX has Step Up mode. First, your current dan rank dicatates the initial pool of charts you get to play; the higher your rank, the harder the songs you'll start with. Second, as you clear songs, the the game gives you harder charts to play, while failing songs will decrease the difficulty of charts allowed. To accomodate this feature, Step Up guarantees three stages, even if you fail your first two.
Shoot Em Ups
- Xeno Fighters has this as of v0.10 in the form of a rank system similar to that of Battle Garegga.
- Raiden, Raiden Fighters and Fire Shark have the tank/gunboat enemies. If you do well enough (survive long enough, amass loads of points, get lots of powerups/bombs), the tanks/gunboats that initially have poor reaction time as well as Painfully Slow Projectiles start shooting you with faster and more accurate shots as soon as they come onscreen. If you're doing well enough, you'll start meeting up with so-called "Sniper Tanks".
- Battle Garegga exponentially increases in difficulty by increasing enemy aggressiveness and health due to a number of factors, such as picking up too many items you don't need and shooting too much. The only way to reverse this? Dying. (Especially effective if it's the player's next to last life.) To make matters worse, every time someone plays the game, the starting rank (difficulty) goes up, and each time the attract mode loops the starting rank decreases. The idea is the more people are playing it the harder it gets, so it can eat more quarters, but if people stop it backs down so a new player will have an easier time and get hooked. However, people figured out that resetting the arcade game also reset the rank. So Raizing fixed this in their next game, Armed Police Batrider. The rank at power-on was the maximum possible starting rank instead! This is a (very infamous) trade mark of Shinobu Yagawa, the programmer of Battle Garegga, Battle Bakraid, and Batrider. These traits are in his later games with Cave, Ibara, Pink Sweets, and Muchi-Muchi Pork.
- In modern Shmups, this is known to fans as "rank" and very common. This has been a feature in shooters since the Japanese release of Zanac in 1986. That game had artificial intelligence that adjusted itself to your playing style. However, the AI wasn't all that bright, and could be subverted by simply firing less. Zanac for the NES got this ass-backwards. The AI level decreased if the player could defeat a boss within the given time limit but increased if the player could not defeat a boss within the time limit.
- Triggerheart Exelica calls this the VBAS (Variable Boss Attack System): basically, this means that the more point medals you collect during the level, the more forms the boss of that stage has and the harder it is. If you have enough, you even have to face a Bonus Boss afterwards.
- In Darius Gaiden, getting a shot powerup will increase the difficulty to the stage's default difficulty.
- Touhou has this is the 4th to 6th games. It gets remarkably less complicated each game. In the 4th game (Lotus Land Story) pretty everything that could be considered playing well raises it, but the opposite is also true, meaning that letting point items fall off the screen makes the game easier. The next game (Mystic Square) has fewer things increase the rank, but the only ways to decrease it are dying and bombing. Embodiment of Scarlet Devil has the rank just keep going up over time and can only normally be decreased by dying. And for some reason it resets to the middle level with each stage. None of the other games use rank, though Imperishable Night lets you start with more lives if you keep continuing.
- In DoDonPachi dai ou jou, using a Hyper will cause enemies to fire more and faster bullets.
- And in DoDonPachi Dai-Fukkatsu Black Label, you get a new Super Mode known as "red mode" in which continuously using it will gradually crank up the difficulty, indicated by a special gauge off to the side of the regular HUD.
- SaiDaiOuJou has a visible numeric rank meter.
- Tumiki Fighters makes the game harder if you try holding on to a large number of enemy ships (thus maximizing your score). If you lose these ships, the bullets immediately thins out.
- Warning Forever adjusts to the player's tactics. If a player focuses on destroying a particular segment of a boss, the next boss will have that section reinforced. If the boss manages to kill the player, it'll have more and better guns of the same type next time.
- The faster you destroy groups of enemies and mini bosses in Ikaruga, the more enemies are generated. The screen is also cleared of bullets when you die, and dying also decreases the difficulty of certain bosses, especially Tageri. The third boss's difficulty is unfortunately bass-ackwards, as it spins faster the longer the fight takes (although it times out after a while).
- The RAY Series also does this. Especially the third game, where the enemies become more abundant and tougher the lower your Encroachment percentage.
- In Chaos Field, if you switch from the Order field to the eponymous Chaos field, your weapons become more powerful, but the bullets greatly increase in speed and density.
- The difficulty of the bosses in Rez increases depending on the player's skill in shooting down enemies.
- Daioh: The difficulty of the game increases depending on how well you do. The farther you go without dying, the more likely it is for the game to become a Bullet Hell.
- Giga Wing: The game's overall difficulty gradually increases until your first death; some players will exploit this by committing suicide at the very start of the game.
- A common variant is to spawn extra enemies (primarily Mooks) if the player finishes off a Mid Boss quickly, which also doubles as a reward (more mooks means more points, more item drops, and/or a longer Kill Streak) as well as a way of filling the time while waiting for the background scrolling and/or Mickey Mousing music to resync with the level again. The Touhou series does this a lot, as well as DoDonPachi Daifukkatsu and Ikaruga.
- A more subtle example in Heavy Weapon. The better you do, the higher your score, and thus the higher your rank. The higher your rank, the more often your airborne foes will drop bombs on your tank.
- After Burner Climax adjusts its difficulty depending on how many enemies you shoot down in a level. If you get more than 50%, you'll earn a star (up to five). Dying brings the star level down by one, and using a continue resets it to zero. More stars = more enemies bombarding you with missiles. However, if you have a full set of five stars when you reach specific stages, you'll access an "S" version of that stage instead of the main one.
- The AI opponents in Wii Sports combine Dynamic Difficulty with Rubberband AI. Get enough home runs in baseball, and they start to make it harder to do in subsequent games, for instance.
- Resident Evil:
- In Resident Evil 4, playing well will increase the amount of spawned enemies and improve their AI; conversely, playing poorly and dying often reduces the number of foes and disables most of their AI. Ammo and health item rarity is also affected by dying.
- Resident Evil 5 has a similar dynamic difficulty mechanic to Resident Evil 4, which has been discovered to use a hidden points system. Basically, the game has 11 separate "sub-levels" for the difficulty level, changing how much damage enemies deal, and how much damage they take from your weapons. Attacking and killing enemies adds points in small amounts (anywhere from 2 points for each hit you deal, to 100 points for a critical headshot), while taking damage or dying subtracts points in larger amounts (from 400 points for a small hit, to 1200 points for dying and continuing). For every 1000 points added or subtracted, the game shifts the difficulty up or down one level. Each of the four difficulty modes (Amateur, Normal, Veteran and Professional) has a minimum and maximum setting, and although some of them overlap, Professional mode is in a league of its own. At the lowest setting, enemies deal half as much damage to you, and take 2.5 times normal damage from your weapons. For the sake of comparison, Veteran mode's highest setting is the second-highest overall, where enemies deal three times normal damage to you, and take 88% normal damage from your weapons. The highest setting, which Professional mode stays at all the time, makes enemies deal ten times normal damage to you. The official guide had an entire section devoted to this system, and how to game it.
- Max Payne claimed to do this. The effect was pretty noticeable on the console versions, but the PC version seemed to be permanently stuck on "as hard as possible". Bear in mind, it had this in addition to three difficulty modes.
- The trope is more obvious in Max Payne 3, where the player receive extra painkillers if they die several times in at the same checkpoint.
- Kid Icarus: Uprising lowers the difficulty every time you die, unless it's already at 2.0 or lower. The hearts invested in the difficulty increase are lost however, and weapons found in the level correspond in power to the difficulty you end on. It doesn't scale up during a level if you do well, but the recommended difficulty for the next level corresponds to how well you did last level.
- X-COM lets you select a difficulty level to begin the game at, and then moves it up or down a notch once per in-game month depending on your score that month. This is rather undermined by an unfortunate bug, which resets the difficulty to the lowest level when you loaded a saved game. Saving and restoring frequently could make the game arbitrarily easy! Even then, the monthly timer has very little effect even without saving and loading; since the game is made up of two executables, it has to save and quit each time you switch from a land battle to the world map (or vice versa). In short, it's impossible to play more than one battle before the difficulty resets to the lowest level unless you patch the game to fix this (using, say, XcomUtil), or use the Windows-based re-release.
- The Super Robot Wars series has Battle Masteries, which are optional, and occasionally difficult, goals to reach in a mission. Depending on how many Battle Masteries (also known as Skill Points) you have at certain points in the game, the difficulty will scale back to Easy, or up to Hard mode.
- Sting Entertainment's two flagship GBA games, Riviera: The Promised Land and Yggdra Union: We Shall Never Fight Alone, reduce enemy Hit Points and other stats (notably, the Rage bar in Riviera) when the player loses. In Riviera, if you lose enough, you won't have to fight the enemies at all (although this doesn't work on bosses, for obvious reasons). Yggdra Union just scales down until a certain minimum point, and then stops (although practically, the player is getting stronger all the time because of how the game handles experience).
- Early in the Wing Commander series, there was supposed to be an adjustment of AI skills, in the games before Difficulty Levels. However, for many there's often little to no notice of much of a difference, in any of the games where this trope was in effect.
- CPU-controlled Jugger from Advance Wars: Dual Strike has this as part of his C.O. Power "Overclock", along with an increase to his positive and negative extremes of his luck modifiers. He has two separate AI scripts in the game, a quite stupid one that he uses normally, and a much smarter one that he follows when his power is active. Of course when you're playing as Jugger, all you get is the luck modifiers. Your DS can't make you stupid when you're not using your CO's powers, after all.
Non-Video Game Examples:
- On the Japanese game show DERO!, the Bomb Room round worked this way. All questions were multiple-choice, and each time the team gets a question wrong, the number of choices on all subsequent questions was also reduced by one. If you did poorly enough, you'd end up facing 50/50 choices, albeit for relatively paltry potential rewards. Some of the other rounds seemed to do this as well, albeit in a less obvious manner. For example, in the Block Word Quiz section of the Beam Room round, a team that was doing especially poorly would often get puzzles with answers only 2 characters long instead of 3.
- Gottlieb's Caveman was a Pinball table with a built-in Video Game. The difficulty of the video game would change based on how well the player did on the pinball board.
- In Star Wars (Data East), shooting the ramp several times lights the Extra Ball shot. The number of shots needed would adjust over time based on how well players did.
- In Safe Cracker, the difficulty of the bank vault board game changes according to how well you were on the pinball playfield.
- It is not uncommon for automated tests to use a binary branching system to determine what the next question will be on a test:
- Registered Nurse (RN) and Emergency Medical Technician (EMT) certification exams both involve branching difficulties. Because of this, if you correctly answer enough questions at the beginning of the exam, they will pass you without requiring you to finish.
- The computerized Graduate Record Examination (GRE) branches, though you do need to finish answering all the questions; it just impacts your final score.