Attack Failure Chance

The simplest Role-Playing Game combat systems have every attack be an Always Accurate Attack. But this trope is for when there's quantified, usually percentage, chances for attacks to fail somehow: misses, gun jams, Magic Misfires, Self-Damaging Attack Backfire, and similar. Missing attacks might also be caused by a Status Effect, usually called "Blind".

And since Always Accurate Attack is for when specific attacks are like that, it means that all games listed there would go here too, since this is the inversion, when attacks can miss, and there's no point in calling out specific attacks, if they're all like that.

Tabletop RPG has a long history of influencing Video Games, such as with 1974's Dungeons & Dragons. This trope is possibly one of its effects. But this trope usually only appears in games where combat doesn't involve controlling the targeting in real-time, since at that point, physics simulation is close enough to reality that making what looks like it should hit, somehow fail in hitting, breaks Willing Suspension of Disbelief a bit.

Since this trope is meant to simulate the unpredictability of combat, how targets can dodge and attackers don't have perfect aim, then a combat system that doesn't have this is possibly saying that its targets somehow can't dodge, or that its attackers do have perfect aim somehow.

The other way of making attacks fail is by making success in attacks tied to success with Action Commands.

Critical Failure will overlap a lot because a random chance of horrible failure for possibly anything, likely includes attacks in that anything. A Breakable Weapons system that includes multi-part weapons like guns or bows, may include a chance for gun jams or string snaps, etc., at high damage levels.

One-Hit Kill attacks are likely to overlap since attacks that instantly kill an opponent are likely to have a high miss rate in order to keep them balanced, and the description of the attack likely notes the increased failure chance, providing the necessary context for this trope.

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Examples:

Tabletop Games

• Chronicles of Darkness: To attack you roll a number of d10s equal to Strength + Brawl - the opponent's Defense (if it's an unarmed attack), Strength + Weaponry - the opponent's Defense (if it's a melee attack with a weapon), Dexterity + Athletics - the opponent's Defense (for thrown weapons) or Dexterity + Firearms (for ranged weapons like guns and bows)^note You don't subtract Defense from your roll in this case because normally one can't dodge bullets. Some powers such as Fate, Space or Time Mage Armor let you dodge bullets and thus subtract your Defense from ranged attacks performed against you, or, in the case of the Celerity Discipline, subtract dice from the attack pool to represent supernatural speed. This represents, for the most part, the attack's chance to miss — partially or completely No Selling an attack is represented by Armor (which, once an attack hits, reduces the amount of damage you take).
• In the d20 System, used by Dungeons & Dragons 3rd-5th edition, d20 Modern, Pathfinder, and Star Wars d20 among others:
  • Attacks are represented by rolling a twenty-sided dice and adding the character's attack bonus to the result, hitting if the total exceeds the target's Armor Class. However, if the dice lands on "1" before attack bonus is added the attack is a Critical Failure, conversely a "natural 20" is an automatic hit and a Critical Hit if it would have hit anyways in some editions.
  • In D&D 3.X and Pathfinder 1st edition arcane spellcasters who wear armor and attempt to cast spells requiring gestures to cast have a percentage chance of failing, represented by rolling a hundred-sided dice or two d10s. In D&D 3.5 and Pathfinder bards could ignore the spell failure chance for light armor and the rule was dropped entirely in later editions of both games.
• In Descent: Journeys in the Dark, attack rolls are made with a dice pool that always includes a blue die with one side featuring a big "X". If the "X" is rolled, the attack fails, regardless of other factors (such as the amount of actual damage and, in case of ranged attacks, distance rolled on other dice in the pool).
• GURPS: Guns will jam on a bad roll; this becomes more likely if the weapon is not cleaned regularly or is poor quality. Shooting without pausing can cause the same problems but heavier barrels warp more slowly and cooling systems allow for basically unlimited fire so long as they work.
• The Unofficial Elder Scrolls RPG: Casting a spell requires a skill test, failing which causes the spell to fizzle out without any effect besides the caster wasting their turn and magicka. A Critical Failure on this test or a failure to cast a powerful or custom-made spell causes Magical Backlash, which can have effects ranging from merely annoying or embarrassing to having to make a test against instant death, depending on the result of a die roll and the power of the spell failed.
• Ars Magica: Ordinarily, the attacker and defender make opposed rolls based on their combat abilities; the attack misses if the defender gets a better roll or the attacker botches. Direct magical attacks are always accurate, so long as the spellcasting roll succeeds, but indirect ones (like magically throwing a non-magical rock) need to be aimed like conventional attacks.
• The Witcher Role Playing Game: Fumbling on a spellcasting roll (getting a 1 on a 1d10) has the spell backfire on the user. This ranges from doing mild damage to causing their focus to explode like a grenade and freezing them/stunning them/setting them on fire.
• The Zweihänder system:
  • Critical Failure: In general, rolling a natural 100 or a high multiple of 11 on any skill test will result in a critical failure as well. A natural 01 or a low multiple of 11 will instead result in a critical success. One during spell casting may summon Daemons of Chaos, render you impotent, render you and your party and your distant relatives impotent, or merely give you an insanity point. Guns tend to simply blow up.
  • It powers Blackbirds RPG: Attempting to cast a Vitiation or a Spell requires a skill test, and critically or sublimely failing this test can cause some horrible effect to the target or the caster, depending on the spell. For example, attempting to magically empower a nearby weapon will instead destroy it on a Critical Failure, or destroy all nearby equipment on a sublime failure.

Video Games

• Seven Sixty Two High Calibre: It has a Breakable Weapons system for its guns, where degradation increases jamming chance.
• In Battle for Wesnoth, all attacks have a chance to hit that depends on the terrain type of the hex the defending unit is standing in. Some Abilities and Weapon Specials change this — for example, Magical attacks always have 70% chance to hit, Marksman attacks have at least 60% chance to hit when used offensively, and the Diversion ability causes flanked units to lose 20% chance to hit.
• Borderlands 2: A chance of Self-Damaging Attack Backfire: Krieg's "Silence the Voices" skill gives him a massive boost to melee damage, at the cost of also giving his melee attacks a chance to hit himself instead.
• Darkest Dungeon: The percentage for an attack to land is determined by a character's Accuracy versus an enemy's Dodge chance, which can be increased or decreased by a variety of buffs, debuffs, and equipment throughout the game. Normally an attack has about a 90 or 95 percent chance to hit, but if that chance is higher or lower due to influencing factors then it will be displayed instead.
• Darkest Dungeon II, along with its' massive overhaul of how combat works, changed the Accuracy and Dodge stats into the universal Dodge tokens. Dodge tokens give a minus 50 percent chance for an attack to land, and Dodge+ tokens increase that chance to minus 75 percent. This way, the player is always able to know exactly what the odds are of their attacks landing without having to calculate a bunch of modifiers.
• Deathloop has a mechanic where several of its weapons can jam if used too often, meaning Colt has to stop in order to un-jam them.
• Digimon Story: Cyber Sleuth and Digimon Story: Cyber Sleuth - Hacker's Memory: Knightmon's Berserk sword, a 30% accuracy Non-Damaging Status Infliction Attack, whose status is Instant Death.
• Diablo (1997), which was based on Roguelikes, based both melee and ranged hit chances on your Dexterity, and if it was low enough, you could forget about hitting anything with your sword or bow. Thankfully, the Dexterity issue was easy enough to fix with enough Level Ups, particularly since Dexterity also governed block chance and ranged damage.
• The Elder Scrolls:
  • The Elder Scrolls: Arena: The manual states that Agility "directly affects your chances of hitting an enemy with a melee weapon".
  • The Elder Scrolls III: Morrowind:
    • While this is a game where weapon targeting is controlled in real time, quantified skill in the appropriate weapon type controls whether the equipped weapon hits or not, since the series was still in transition from its Faux First Person 3D roots.
    • Spells failing to be cast happen by chance if magic skill levels are below a threshold. The more the spell costs in Magicka, the harder it is.
• The Fallout series:
  • Fallout: The manual says and implies a lot:
    • Agility and the Small Guns skill matters in hitting enemies with small guns:
      The higher your Small Guns skill the easier it will be for you to hit your target
    • The Jinxed trait's description mentions the existence of Critical Failures doing things like making the held weapon explode, a.k.a Self-Damaging Attack Backfire.
  • Fallout 3: VATS attacks change the game from a Third-Person Shooter where the player's aiming skill matters, into a state where time is paused and reminiscent of the Turn-Based Combat of previous games in the series, where body parts are targeted with percentage hit chances, with a maximum accuracy of 95%.
• Far Cry 2's gunplay includes the ability for any weapon in the game to jam or break, necessitating finding new weapons if you don't want to die.
• Final Fantasy features this in general, but Final Fantasy Tactics makes a big deal out of it. First off, body armor does not provide Damage Reduction as it does in other games in the franchise; it instead provides a combination of Body Armor as Hit Points and increased likelihood of evasion. Second, as a tactical RPG, positioning is important, and an opponent's dodge chance is dependent partially on whether they are facing you, at a 90-degree angle to you, or facing away. As such, every ability comes with a confirmation screen which includes the associated Attack Failure Chance, expressed in percentages.
• Fire Emblem: Devil weapons, like the Devil Axe and Devil Sword, have a chance of Self-Damaging Attack Backfire. In Fire Emblem Gaiden, there is only the Shadow Sword, since axes don't exist in the player's hand, which has a similar effect to the Devil Axe, but Dread Fighters are immune to it. In most games, the backfire rate is decreased by the unit's Luck stat, but, in Fire Emblem: The Binding Blade, it is decreased by the unit's displayed Level instead. Regardless of the reduction, Devil weapons will always have at least 1% to backfire. Hope you don't get a critical hit when the Devil Axe backfires. Since Fire Emblem Fates, Devil weapons decrease your HP when you attack with it.
• In Helbreath, casting spells has a chance of failure. Magic stat decreases the chance of failure.
• In Jagged Alliance 2, guns degrade and will jam or misfire when degraded, but only for the player.
• In its very early years, League of Legends had a universal stat known as "Dodge", implemented as a sort of inverse to "Critical Hit Chance" that allowed certain characters to randomly shrug off basic attacks to receive no damage. Only one champion had innate Dodge as part of their kit — Jax, whose ability "Counter Strike" granted him Dodge over several seconds before retaliating based on whatever damage he absorbed — for everyone else, it was only granted in single-digit amounts from various Runes and Summoner Masteries as well as from the item "Ninja Tabi" (a set of boots that granted a 12% Dodge chance). There also existed the "Sword of the Divine" item designed to counter the stat, having an active buff to completely bypass Dodge and deal full damage all the way. Dodge was eventually removed from the game in 2012 as it wasn't fun on either end of the exchange (frustrating attackers to lose damage at random, unsatisfying and unreliable for targets), with Jax's "Counter Strike", Ninja Tabi, and Sword of the Divine all being majorly reworked (the latter item removed altogether by late 2014).
• Magia Record: Puella Magi Madoka Magica Side Story: Some Memoriae and Spirit Enhancements may give characters a chance to Evade attacks, with the source with the highest percentage of Evade taking priority after it was nerfed to keep them from stacking on each other. There are also three status ailments (Fog, Blind, and Bewitch) that can cause affected characters to have anywhere between a 25%, 35%, and 50% chance to miss an attack, and unlike Evade, are able to stack with each other. Naturally there are some methods to bypass Evade and the mentioned status ailments, such as the Anti-Evade status effect, or by simply using a Magia or Doppel disc instead of regular discs.
• Mewgenics: Attacks are normally of the always accurate type, but the attack is given a chance to miss its target if it is hiding in tall grass. However, the grass tile itself isn't capable of dodging, so if you set the grass your target is on ablaze...
• Miitopia: Some One-Hit Kill attacks:
  • Clerics learn the Righteous Anger move at level 19. With a success rate of 50%, it banishes an enemy regardless of its remaining HP.
  • At level 23, Imps learn "Demonic Whisper", which attempts to one-shot every enemy. In exchange for targeting all enemies, its success rate is a paltry 20%.
  • Chefs can learn Monster Dinner at level 30. With 50% probability, it instantly turns the enemy into grub.
• Minecraft Dungeons has the blindness effect, which gives the player a chance to miss their attack and not deal any damage to targets they hit. The effect can only be obtained through one of the illusioner's attacks or getting inked by a squid.
• Monster Rancher: No move is 100% accurate. The likelihood of an attack hitting at all will depend on a monster's accuracy stat and the speed stat of the opponent.
• Pokémon:
  • Some moves don't have accuracy of 100% or greater, and if an attacker had their accuracy lowered or the defender had their evasion increased, that can make what was labeled as 100% accurate attacks, miss instead. Pokémon Red and Blue has the 1/256 accuracy glitch that gives all attacks that possess an accuracy stat, that specified chance to miss.
  • The confusion status effect gives every move, even Always Accurate Attacks, a 33% chance of failing, with the user damaging themselves instead. The paralysis status effect, meanwhile, gives every move a 25% chance of failing.
• Prayer of the Faithless: Offensive actions in this game never miss outside of the target having a counter stance. However, the Skill stat determines the chance for an attack to graze the target and deal less damage.
• In Runescape Classic, there was a chance for spells to fail. When the spell failed, the player had to wait for 20 seconds to cast the spell again.
• StarCraft: Most attacks automatically hit, but land units shooting uphill were penalized with a 30% miss chance.
• Titan Quest: The player can make their enemies' melee and spell / projectile attacks miss, by increasing their "Chance to [Dodge Attacks / Avoid Projectiles]" statistics.
• Toontown Online:
  • Certain SOS Cards can guarantee that Toons will guarantee their attacks land every turn. There are also attacks that guarantee the Cogs' attacks will miss every turn. ^note An update to Toontown Rewritten nerfed this, so this instead modifies the accuracy instead. Toontown: Corporate Clash removes SOS Cards entirely, replacing them with I.O.U.s that instead boost the damage of certain gag tracks. The star rating of the SOS card will determine how many rounds this will last.
  • Getting damaged from Trap, Throw, Squirt, or Sound in the same turn will buff the accuracy of Drop.
  • In Toontown: Corporate Clash Zap will miss entirely on unsoaked cogs. You need to attack a cog with Squirt, which soaks adjacent cogs as well.
  • Online and Rewritten allow Toon-Up to miss, unlike in Toontown: Corporate Clash. If the Toons give lowercase chuckles, it missed, but if there's at least one capital letter in the laugh, it landed.
• A Very Long Rope to the Top of the Sky: The tutorial shield of Buckler explains how shields relate to evasion:
  Shields naturally give ten percent additional evasion.
• View from Below: Despite the timed hit system for normal attacks, the player's normal attacks have a chance to miss even if they press the button in time for a "Great" or "Perfect" hit. The player can buy an accessory, Blessed Ring, to decrease the miss rate of normal attacks.
• The Exidy Sorcerer game Wizards Castle: An attack hits if the player's dexterity value is greater than a randomly generated number from 1 to 21, or 4 to 25 if they're blinded. Dexterity can be from 1 to 18, with zero dexterity equalling death.
• With guns, or ARMs being one of the most notable weapons in the Wild ARMs games, accuracy is a bit of an issue. If an ARM has low accuracy, then there's a higher chance its attacks will miss. (The most notorious for this is Rudy's Wild Bunch ARM in the original game.) Upgrading ARMs can mitigate this, as can the Lock-On force (if a character has it).
  • In some games, ARMs can malfunction. This can happen to Jude in the fourth game, as well as to Rudy in the remake of the first game.
• XCOM 2 has a mechanic known as Dodge that applies to several enemies, as well as XCOM soldiers with the right gear. Dodge is a percent chance that isn't shown to the player, takes priority over critical hits, and enemies that Dodge take partial damage from the attack with the message "Dodge-Grazed" appearing when the damage pops up. The 1.0 version of the game allowed this to happen even on shots that had a 100% chance of being hit.

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