Limited Move Arsenal

The brain is a remarkable device. With training, it is capable of processing and accumulating an essentially unlimited number of skills.

In video games, this can be hard to simulate.

Either the controls of the game make it impractical to have access to more than a certain number of moves at a time, or having too large a selection of skills at one's disposal would simply make the game too easy. As a result, characters are forced to rely on a strictly limited move set, rather than being allowed to draw upon all the skills they have learned at any time.

Comes in two flavors:

Characters have an inventory of skills, out of which they can "equip" a limited number to be available to them in combat, as if they were items. You may or may not be allowed to change your setup mid-battle.
Characters are allowed to know only a limited number of skills at any time. When they learn new skills, they are forced to forget others to make room.

Examples of Limited Move Arsenal include:

Examples of Type 1

The Star Ocean games
Monster Rancher 1 and 2
Tales of Symphonia is type 1 for melee. You can change the skills mid battle, but unlike spells (where the entire list can be activated via menu) you can only activate melee techs from a shortcut.
- And even spells can only be menu-activated on computer-controlled characters.
- The Tales games, starting with Phantasia have the main character equip four skills to use in battle among the dozens of techniques they learn. With the combo command item, they can use any of these by inputting a series of fighting game-style commands.
zOMG: the player can only equip 8 rings at a time.
The first two Paper Mario games. You can only equip a limited amount of badges. You can increase the amount with level up bonuses. The first one had a cap of 30 badge points, while the second ignores the cap and still allows you to get bonuses after that.
Final Fantasy Tactics, Final Fantasy Tactics Advance, and Final Fantasy Tactics A2. Each job has a set ability, and you can set a second ability (either items or another job's set ability), a reactive ability, and a passive ability. Alchemists can equip both Items and a second job set, though the Items are locked in place and can't be exchanged for a third job set.
Legend of Mana, with separate pools for combat maneuvers and special attacks.
Final Fantasy V, with a system that probably formed the basis for the one in Final Fantasy Tactics.
Final Fantasy IX, with regards to passive skills.
Diablo presents a somewhat annoying case, in that one can only have two skills ready at any one time. For passive skills like Paladin auras, this makes sense, but for normal attacks and spells it's very limiting. The game also lets one assign skills to quick keys, but these only ready skills, actually activating them requires a press of the slot's button.
The World Ends With You.
SaGa Frontier and SaGa Frontier 2.
Guild Wars
- Specifically (if you've got all the campaigns), your skill inventory contains what you've learned of the average of 90 skills of your primary and secondary professions that you've bought, plus what you've captured of the ~25 elite skills for each profession, plus up to ~50 reputation-based Player Versus Environment only skills. And to make your choices larger, you can learn to change your secondary profession at will. You can equip: eight skills. Including only one elite and no more than three PvE.
Devil Survivor for humans limits the human character to a set number of spells/skills and support abilities, and you can only have one of any given ability between all of them. Demons are type 2.
Final Fantasy does this a lot. In addition to the above I and III had limited spell slots (III three also restricting thing based on job), VII tied abilities to items (which in turn had slots dependent on equipment), VIII has limited command and passive slots (the abilities themselves gained from type 2 summons), and X-2 only lets you use the abilities of any one dresssphere at a time (with the ones you can switch to limited by plate you equip). Yeah, this is kind of Final Fantasy's Characteristic Trope.
- Then again, some of the franchise's avert this trope completely. Final Fantasy X and Final Fantasy XII allow every character to learn and equip every skill (with few exceptions), though X does allow one to equip only four abilities each for offense and defence.
Breath of Fire: Dragon Quarter: 3 skills of each of 3 levels. Fewer on some weapons.
Eternal Sonata initially limits you to having one active special move in light and one in shadow. Later the limit is increased to two of both.
In Infinite Undiscovery, battle skills are limited to two slots. Even for the (friendly) AI characters who are not restricted by the lack of controller buttons. Magic spells are not limited.
God Hand gives the player a limited number of slots for Gene's moves. It can be increased by purchasing Items from the shop.
Devil May Cry 3 allows Dante to use one of six Styles, sets of secondary actions used with the Circle button, including extra moves with his melee weapons or guns, evasive maneuvers, the ability to parry attacks and release the built-up energy, summoning a phantom that a second player can control, or slowing down time for everything but himself. The problem is that only one of these Styles can be used at a time, and you can only switch Styles at a pedestal where you use Orbs to buy items. DMC4 added the ability to switch Styles on the fly when playing as Dante.
Immortals in Lost Odyssey can learn every skill in the game (except enemy-only skills), but can only use a limited number at a time, depending on the amount of "slot seeds" they've used and a few skills that give extra slots.
Dubloon
Valkyrie Profile and its sequels. While the particular mechanics were different in each game, you could only equip a limited number of skills at once, although each character could potentially learn every non-weapon skill and each skill related to weapons that they could equip.

Examples of Type 2

Every Pokémon game, including the spin-offs, limits each of your Pokémon to four moves at a time. Whenever one of them already has four moves and is preparing to learn another, you have to choose which move your Pokémon should forget, or just cancel learning the move.
- Junichi Masuda, game director and one of the composers for the Pokémon games, once stated that during the development of Pokémon Ruby and Sapphire, two things brought under consideration were potentially changing the number of moves that a Pokémon can learn and the number of Pokémon that a player can have with him/her at a time while traveling; however, none of these have been altered as of Generation V.
You can only have 20 skills on any given character or item in Phantom Brave.To learn more, you need to have a Witch remove older ones beforehand.
Monster Rancher 3
Shin Megami Tensei games have this. Each Demon/Persona can only have so many skills.
- With the exception of Digital Devil Saga, which was type 1.
Tales of Symphonia is also type 2 as most moves/spells come in pairs and you can only know one of them at a time (for example, Genis's Thunder Blade and Spark Wave) depending on you exsphere configuration. (barring glitches).
Referenced in this VG Cats comic.
You were limited to 64 skills per character in Breath of Fire III. Not only that, but you could only have one copy of a skill on one person at a time, and you had to use a rather rare item (which could thankfully be farmed) to transfer skills.
Final Fantasy II limits each character's magic spells to a certain number.
The SD Gundam G Generation series of games limited characters to four attacks up until G Generation Spirits, at which point the number jumped to six.