History GoodBadBugs / TurnBasedStrategy

** When [[VideoGame/FireEmblemRadiantDawn Lucia]] was added as a unit, her weapon's effect had a form of NoSell that prevented out of combat effects or skills from applying to her. A mistake with the coding though caused the effect to only half apply to her allies, meaning an ally unit with one of the Save skills meant to shield allies would protect her, but Lucia would still be able to counter the attacker and not be hurt. This briefly made her insanely broken as a result, leading to it being fixed quickly.

*** There is a pretty famous one involving the skill Adept. Adept gives the unit a speed percent chance to make another attack, meaning it has a somewhat low but still decent chance to hit when using a unit with good speed. If using a Brave weapon though, Adept will still have a chance of activating on the extra attacks as well. Where it becomes almost certainly a bug is that if a character has the Resolve skill - which gives a 1.5 multiplier to speed and skill if below half HP - then the character has a huge chance of making ''every attack'' activate Adept, meaning instead of up to four attacks, the unit can make ''eight'', which can make almost every enemy in the game crumble unless they have insanely high defense or some kind of NoSell.

* The first ''VideoGame/SuperRobotWarsOriginalGeneration'' game had a bug that caused all character themes to be overriden by a particular enemy unit's theme when he comes into play. The theme was so SugarWiki/{{Awesome|Music}}, however, that the feature, now dubbed "Trombe Override" (after [[https://www.youtube.com/watch?v=BvbkVAnpcR4 the theme music, named ''Trombe!'']]) is a regular fixture of the series.

** ''VideoGame/SuperRobotWarsZ Tengoku-hen'' has a glitch where if either [[Characters/SuperRobotWarsZ Hibiki Kamishiro]] or [[Anime/{{Diebuster}} Nono]] use items in their inventory and then transform into their super modes, they can reuse the items that they already have used again. By the end of the game, both of them each get an even ''more'' super mode which also has the glitch, letting them use their items a third time. This wouldn't be so broken if ''Tengoku-hen'' wasn't the only game to ever feature the Miracle Fragment, an item that casts every single beneficial spirit command in the game, making it already a GameBreaker when you can use it ''once''.

** ''VideoGame/SuperRobotWarsZ Tengoku-hen'' has a glitch where if either [[Characters/SuperRobotWarsZ Hibiki Kamishiro]] or [[Anime/{{Diebuster}} Nono]] use items in their inventory and then transform into their super modes, they can reuse the items that they already have used again. [[GameBreaker And considering the both of them]] have 3 tiers in their super modes (though Nono gets hers near the end of the game).

*** There is a pretty famous one involving the skill Adept. Adept gives the unit a speed percent chance to make another attack, meaning it has a somewhat low but still decent chance to hit when using a unit with good speed. If using a Brave weapon though, the game can proc Adept on the the extra attacks as well. Where it becomes almost certainly a bug is that if a character has the Resolve skill - which gives a 1.5 multiplier to speed and skill if below half HP - then the character has a huge chance of making ''every attack'' activate Adept, meaning instead of up to four attacks, the unit can make ''eight'', which can make almost every enemy in the game crumble unless they have insanely high defense or some kind of NoSell.

** There is a pretty famous one involving the skill Adept. Adept gives the unit a speed percent chance to make another attack, meaning it has a somewhat low but still decent chance to hit when using a unit with good speed. If using a Brave weapon though, the game can proc Adept on the the extra attacks as well. Where it becomes almost certainly a bug is that if a character has the Resolve skill - which gives a 1.5 multiplier to speed and skill if below half HP - then the character has a huge chance of making ''every attack'' activate Adept, meaning instead of up to four attacks, the unit can make ''eight'', which can make almost every enemy in the game crumble unless they have insanely high defense or some kind of NoSell.

*** Seemingly to avoid any issues, Staff weapons are capable of being used as melee weapons, though only if the user is attacked. For some reason though, most Staffs have higher than average crit chance, with the Matrona staff having a guaranteed crit chance. Due to this, it is possible with some preparation to have a character crit enemies to death with what amounts of bonking them with a healing staff, despite the game obviously not intending for that to be a strategy.

*** Seemingly to avoid any issues, Staff weapons are capable of being used as melee weapons, though only if the user is attacked. For some reason though, most Staffs have higher than average crit chance, with the Matrona staff having a guaranteed crit chance. Due to this, it is possible with some preperation to have a character crit enemies to death with what amounts of bonking them with a healing staff, despite the game obviously not intending for that to be a strategy.

*** When randomly generating units for the training tower or Tempest Trials, ensures that legendary weapons or [[SecretArt exclusive skills]] don't go into the unintended hands. An oversight on the weapon Alondite caused one of its wielders, Zelgius, to randomly generate with a random non-legendary sword in the training tower and completely unarmed in Tempest Trials, because Alondite was coded only for the Black Knight. This was eventually fixed in 2.3 as an undocumented change.

* In ''VideoGame/RomanceOfTheThreeKingdoms IV: Wall of Fire'', one can transform a number of soldiers into a nigh-infinite number of soldiers by assigning them to a general's command and then declining to go to war, removing the general and reassigning him, and repeating as desired.

*** Staffs were given battle animations so that if one using it is attacked, the game doesn't have issues loading the animations. As a side effect of this though, they had to give them some amount of stats to make it work. Likely because they couldn't do damage normally, staffs were given high crit chances (as in higher than weapons designed to actual crit enemies). Several units who can use staffs also have decent strength stats, meaning its possible to kill enemies by criting them with a staff.

** A less "glitchy" bug is the way the AI is coded to refuel units. The AI is indeed coded to move units adjacent to an APC to refuel them if they get low on fuel, but this is bugged because the AI is also coded ''to move transports last''. This means they'll move their own units beside an APC, then the APC will move way, then the turn will end, and if left alone they'll effectively chase their own [=APCs=] about the map until they run dry on fuel. This actually makes ''Drake'' an incredibly useful CO on the Green Earth factory mission and the final missions of ''Advance Wars 2: Black Hole Rising:'' since his Super CO power drains half the fuel of his enemy, you can put a large swath of Hawke and Sturm's army into this glitched "chase the APC" behavior which renders them incredibly vulnerable to attack.

** Advance Wars Dual Strike had a means of glitching the game to have no [=CO=] at all, resulting in a glitched "commander" who had Andy's theme, no [=CO=] power, and [[MasterOfNone completely average stats with no unique abilities]]. Being able to choose no [=CO=] for your army would even [[AscendedGlitch become a feature]] in Advance Wars: Days of Ruin.

** ''VideoGame/{{Super Robot Wars Z}}2'' had some interface tweaks between the first and second parts. One of the tweaks opened up a bug that allows you to have ''[[LoadsAndLoadsOfCharacters all of your party members]]'' take a turn at using the Sub Orders system, instead of the normal limit of twenty. While this can be used to gather enormous amounts of money very quickly, a less game-breaking application is to gather kills and PP on the units that you don't normally deploy on a given run. Another bug allows you to select and then deselect the carryover option when starting a new game to stack the carryover bonus money, allowing you to gain enough money to max out all of your units before the game even begins.

** In ''VideoGame/FireEmblemGaiden'' the player is normally expected to have TheHero [[OnlyTheChosenMayWield use]] the SwordOfPlotAdvancement in order to damage the FinalBoss after a certain point because said sword is a VillainBeatingArtifact. However, a programming oversight that normally forces attacks to miss (as the force the player into beating the final boss in the intended way) fails to work on the [[LifeDrain Nosferatu]] spell, which has fixed accuracy. As a result, it became possible to kill Duma with Nosferatu, which was eventually added in as an EasterEgg when Gaiden was remade.

** In ''VideoGame/FireEmblemGaiden'' the player is normally expected to have TheHero [[OnlyTheChosenMayWield use]] the SwordOfPlotAdvancement in order to damage the FinalBoss after a certain point because said sword is a VillianBeatingArtifact. However, a programming oversight that normally forces attacks to miss (as the force the player into beating the final boss in the intended way) fails to work on the [[LifeDrain Nosferatu]] spell, which has fixed accuracy. As a result, it became possible to kill Duma with Nosferatu, which was eventually added in as an EasterEgg when Gaiden was remade.

** In VideoGame/FireEmblemTheSacredStones, that enemy control glitch (which can now be activated by normal combat damage as long as it's the enemy's turn) still lets you make all the enemies hand their weapons and equipment to your team. Including, say, claws, teeth, and eyes, which the game treats as weapons. And if you then equip eyes, you can train any character, no matter their class, in dark magic. You can also give rare items to a gorgon egg, which will mark its whole inventory except the first item as "items which will be dropped when I die", wait for it to hatch, and kill it, and when you do all the items will be fully recharged, even the unique items which were specifically designed to be unrechargable.

*** When randomly generating units for the training tower or Tempest Trials, ensures that legendary weapons or [[SecretArt exclusive skills]] don't go into the unintended hands. An oversight on the weapon Alondite caused one of its wielders, Zelgius, to randomly generate with a random non-legendary sword in the training tower and completely unarmed in Tempest Trials. Turns out Alondite was coded only for the other wielder: [[spoiler: his alter ego,]] Black Knight. This bug was fixed in 2.3, but wasn't documented.

** Civ I gave the AI single blanket aggressiveness ratings. The Democracy government made your citizens unhappy with war, so it gave a modifier of -2 to the rating. This worked pretty well at making them less likely to start trouble, except that [[UsefulNotes/MahatmaGandhi Gandhi]]'s [[ActualPacifist default aggressiveness was 1]], and would underflow to 255, so as soon as he got democracy he would turn into a bloodthirsty maniac that threw nukes around with reckless abandon. (By way of comparison, the most warlike leaders were Montezuma and Genghis Khan, with aggressiveness of 10.) This was so memorable that [[AscendedGlitch later games in the series give Gandhi an abnormally high priority on the construction of nuclear weapons]].

** In ''VideoGame/FireEmblemRadiantDawn'', an enemy Bishop with a Rescue staff can place an enemy on top of a pitfall trap in Chapter 3-11. This allows a unit with Pass to move through the square unimpeded, as well as creating a very silly situation where a unit can engage an enemy and then fall into a pit as soon as they try to pass through the recently occupied space. More importantly, you can take advantage of this by placing your ''own'' flying units atop one of these spaces (and you recruit a LOT that chapter) and then moving your non-fliers past the pitfalls. The game will not allow two units to occupy the same space; therefore, it will not stop them as they go over the pitfalls.
** ''VideoGame/FireEmblemHeroes'', when randomly generating units for the training tower or Tempest Trials, ensures that legendary weapons or [[SecretArt exclusive skills]] don't go into the unintended hands. An oversight on the weapon Alondite caused one of its wielders, Zelgius, to randomly generate with a random non-legendary sword in the training tower and completely unarmed in Tempest Trials. Turns out Alondite was coded only for the other wielder: [[spoiler: his alter ego,]] Black Knight. This bug was fixed in 2.3, but wasn't documented.
*** Also in Heroes, on the first Touch Battle, it was possible to win the first level without actually playing, as you had just enough HP to tank all the enemies.

*** When founding a Pantheon, you receive a small bonus to go with it. However, if you press Escape at the same time as clicking 'Found Pantheon', you get the founding bonus but can choose another one. Or the same one. Repeat this as many times as you like for as big an early-game steroid as you like, such as having fifty Settlers on Turn 30.