A point in a video game where a certain weapon or ability is not actually taken away or crippled or disabled in any way or fashion in story, but merely unusable or unselectable to the player for no particular reason given by the game, or a very weak reason in the form of a handwave. Different from Gameplay and Story Segregation, in that there is no in-story explanation for it. You just plain can't use/select it now; you can probably use it later, just not at the moment. Even when all logic the game has laid out indicate they are fully capable of doing what you're not allowed to do. Closely related to the Insurmountable Waist-Height Fence and its sub-trope the Invisible Wall wheras this trope deals with what the player can/can't do, not necessarily relating to the terrain.
Possibly justified by the developers as a way to not make the particular part cheap or too easy, or because it would possibly be too much work to program. Yet they make little to no effort to justify it in story and/or context.
Video Game Examples:
- The Legend of Zelda: Ocarina of Time: When you finally become Adult Link, Navi informs you that some items and weapons you hold can't be used as an adult, just because. This basically accounts for nearly everything you have from your long ranged slingshot, to your stunning boomerang, to even Deku Sticks. The real-world reason for this is to prevent you from Sequence Breaking with your old puzzle-solving tools. But really, it does seem ridiculous that Link can't use any of his kid weapons or wooden sticks for that matter?
- In The Wind Waker, when fighting the flashback bosses in the last Dungeon, Link is restricted to whatever equipment he had at the time.
- Metroid: Other M: Other M's justification as to why you're starting from scratch with power-ups: Samus refuses to use her perfectly-functioning weapons and abilities until Adam, her (temporary) commanding officer, gives her permission. While this can be hand-waved as being for safety purposes, so her super missiles don't accidentally blow up the station, it makes zero sense when she dies from heat exhaustion in lava-filled rooms because Adam has not yet told her, "Hey, you should probably turn on your heat-resistant Varia suit now."
- Brütal Legend: Eddie can never use his wings outside of Stage Battles, his demon side conveniently comes out only when a Stage Battle calls.
- Also note that the normally gorn-tastic insta-kill Facemelter Solo seems to merely heavily damage certain units in said Stage Battles in story mode. Though we know this was merely a case of nerf.
- Treasure Planet: Battle at Procyon: The player is not able to buy Heavy Plasma Cannons in the campaign when the difficulty is set to hard, despite the Royal Navy normally having access to Heavy Plasma Cannons. This is most noticeable when the player is given a Fast Frigate, which comes with a Heavy Plasma Cannon by default, but if the player switches the Heavy Plasma Cannon for a different weapon on hard mode, they cannot get it back.
- In several of the Dragon Quest games, you have access to a full-party full-heal spell that is, for no reason that is ever stated, available in battle but not the main menu. Likewise, there's a nifty item called the Sage's Stone which is a full-party mid-heal which can be used infinitely for no MP cost... which is also available only in battle. You want to heal up your party on the field, you've got to use spells that eat up more MP than the other options would.
- In Final Fantasy IV, child Rydia can use white magic but adult Rydia cannot. Why? We're not sure.
- Final Fantasy XII. The License System in the game requires the player to spend a form of experience points to teach individual characters how to use equipment (or access spells and some inherent stat/ability boosts). For advanced weapons and armor this kind of makes sense, but the License System also covers any and all Accessories (like various hats, boots, hair clips, etc)
- Final Fantasy XIV: The level-synch feature kinda has that effect, temporarily lowering the players level to be within the range of levels intended for the dungeon or FATE in question. In addition to lowering stats (including those of equipment) this can temporarily lock you out of abilities you have unlocked at a higher level, though you get to keep your chocobo companion and job below level 30.
- In Kingdom Hearts Sora learns to fly near the end of the Neverland level. While he does gain the Glide ability afterward he can only fly freestyle in Neverland and certain boss battles near the end of the game. From a story standpoint he should maintain the ability. You can't even argue that he runs out of pixie dust since Peter Pan has Tinkerbell go with him.
- Kingdom Hearts: Birth by Sleep: You are unable to D-Link in the Mirage Arena, even in single player.
- Most equippable items in Kingdom of Loathing have a minimum requirement for one of your stats. This generally makes sense for weapons, but for clothing and "accessories" it's a little baffling. Due to "ascension," you will often find yourself with a huge stockpile of powerful items that you cannot use until you level up again. Of course, this is a game where you need a special skill to wear shirts because you don't initially realize that you have a torso, so it's probably not meant to be taken too seriously.
- Assassin's Creed II: In Secret Locations such as the Assassin's Tombs or Templar Lairs, you are unable to equip your two long ranged weapons; your throwing knives or hidden pistol. No explanation given by the game, they're just grayed out in the weapon select menu. This is possibly made so that killing certain mooks to trigger cutscenes from afar wouldn't be possible. Not that you even need them to dispose of guards, but it's still a little ridiculous when you can't simply lock on and chuck one or two knives at a running guard or just take careful aim and Just Shoot Him In the Back. But nope, the guard is 100% invincible on all occasions until he reaches the end of the chase, even if you somehow get close enough to tackle-stab him, the game never lets you.
- In Metal Gear Solid, you have access to chaff grenades, which are usually able to knock out all security cameras. However, within Communications Tower A, your chaff grenades become useless for no reason other than to allow a specific surveillance camera to alert a cavalcade of guards to chase you up the tower. It only occurs once, and returning to the area later does not trigger the event again. In The Twin Snakes, it was removed and Snake trips a motion sensor instead.
- There is exactly one part of Metal Gear Solid 2 where you can have a cardboard box but not equip it; the section in question is a side-scrolling run along a walkway, where standing up can get you spotted while staying low means you're too slow to avoid the falling platforms. As the box halves your height but doesn't affect your movement speed, using it would make the section too easy.
- Alone in the Dark (2008): During a light based puzzle section near the end of the game, the flashlight Edward Carnby has throughout the entire game suddenly becomes unusable until after the puzzle is solved.
Non-Video Game Examples
- In the Deckbuilding Game Hero Realms, the players do have certain item cards such as a Dagger and Shortsword. However the items don't stay in play, can only be played when drawn, and are just discarded at the end of the turn. There's no reason given as to why the player can't use their weapons at any time.