Experience

Experience, or EXP, are obtainable reward points as part of a vital, in-game system by which certain characters can progress through the game via level up. The system has a set number after each level up which has to be completely depleted to zero in order to progress to the next level. The set number can slowly be depleted after defeating enemies, and different enemies provide different amounts of experience once they are defeated. The set number increases after each level up, therefore meaning harder to reach the next level. Tech points are also obtainable reward points and work like experience points but are awarded when the player uses various techniques in battle, like deflecting blows or exploiting enemy weaknesses.

Mechanics
In most games of the series, the experience gained from each defeated enemy is the product of a base value unique to the enemy type, a value based on the scenario's "Battle Level", and any modifiers on the player character, such as those granted by EXP Boost, Hi-EXP Boost, Experience Boost, Double EXP, the EXP Necklace, the EXP Earring, the EXP Ring, or the EXP Bracelet. Upon acquiring experience, a counter appears on the HUD displaying the amount earned from the battle, as well as the experience required to reach the next Level; generally, the amount gained from a specific enemy will also appear over that enemy as they fade away.

In Kingdom Hearts, there are only two effective Battle Levels, distinct from those used to depict the average difficulty of the scenario: before Kairi's rescue, and after it. Instead of being a product of an enemy's individual value and the scenario's battle level, each type of enemy has two individual experience values. The values used before Kairi's rescue are generally staggered to provide increasingly rewarding battles as the player makes their way towards Hollow Bastion, while the values used after her rescue are more equalized, to make battles in each world approximately as rewarding as in any other.

In Kingdom Hearts: Chain of Memories, the system is halfway between the original system and those used in later games. Each enemy has an individual experience value for each floor of Castle Oblivion that it can appear on, with more experience being rewarded as the player makes it farther to the end of the game. Furthermore, experience is not directly awarded to the player character upon an enemy's defeat; instead, they drop Experience Prizes, similar to HP Prizes in other games, which the player character must pick up in order to acquire. These prizes fade away if left on the field, making it possible to miss them, but any prizes still on the field when the battle ends are automatically picked up.

Kingdom Hearts
In Kingdom Hearts, leveling up can be done easily by juggling Rare Truffles; they drop large amounts of experience after 100 juggles, which equate to around 5050 EXP points.

For those without the patience to juggle Truffles, quick leveling can be done via repeating Seeds 10-1 in the Hades Cup repeatedly until the player reaches level 70, at which point they can easily complete the Time Trial for the Hades Cup. Doing so allows Sora to "choose" who you wish to fight. Repeatedly defeating the Rock Titan is another good way to gain experience, as it awards 4000 Experience, and about 100 Technique, or Tech, experience per defeat.

For those who haven't completed the Time Trial and don't have access to the "choose" feature, repeated Ice Titan conquering is also decent, and actually better if the player doesn't care about what level their companions are, or if they have Strength under 55. The Technique experience gained from the Ice Titan is almost equal to the amount received for defeating it, although the fight takes a little longer and is harder for some. It's excellent for leveling Sora up by himself.

Kingdom Hearts Re:Chain of Memories
In Kingdom Hearts Re:Chain of Memories, best location to gain experience for is Destiny Islands, using a Deck made of Mushu and Fire card. The player needs to have obtain the Mega Flare Sleight. Upon entering a battle, immediately stack a Mushu and two Fire cards in order to create Mega Flare. After defeating them with Mega Flare, a new horde of enemies will appear. After defeating swarms of enemies, the player will gain around 2000 experience per battle. Using a 'Teeming Darkness' room card is recommend due to the increase of Heartless within the room.

Kingdom Hearts II
In Kingdom Hearts II the best location to level up at is the peak of Pride Rock. Swarms of Rapid Thruster Heartless spawn repeatedly here which makes leveling up simple with long combos and Magnet-Thunder.

Another excellent place to level is to go to through the Castle That Never Was with Experience Boost and the Gull Wing Keyblade equipped, while using a high-level Drive Form. The player should turn off Donald's Donald Cure ability and allow himself to get hit until the HP bar is flashing red. The experience gained will be from 1500-3000 points per Nobody. It should be noted that this method is risky if Sora is not at a high level.

Kingdom Hearts Birth by Sleep
The best location to gain experience for all three characters is the Reactor in Radiant Garden, using a Command Deck with four Mega Flare Commands. The player needs to have the ability EXP Chance activated and his/hers health must be below 25%. The player should also take off every Treasure Magnet ability the player has equipped, and go to center of the Reactor. Unversed will spawn at this point. After defeating them with Mega Flare, a new horde of Unversed will appear. After defeating multiple swarms of Unversed, the player will gain around 1600 experience points. Equipping a Keyblade that has a high magic stat is recommended, such as the Brightcrest for Aqua, No Name, Pixie Petal, or Ultima Weapon.

A location for Ventus and Aqua to gain experience is the Launch Deck in Deep Space. The player should make sure that the Mickey Dimension Link has its second emblem, as it provides Double EXP. The player must exit from the Machinery Bay Access save point and walk forward until enemies appear, then summon the Mickey D-Link right away and defeat the Unversed. After defeating the multiple swarms of Unversed, the player will gain around 2000 and 3000 experience points.

Another strategy is to meld the EXP Walker ability and fight Unversed, while at the same time walking and avoiding using Movement Commands, such as Cartwheel, Slide, etc. This will make the player receive the optimum amount of experience in an average battle. The player can also use it with EXP Chance to allow a larger EXP revenue.

Kingdom Hearts Re:coded
In Kingdom Hearts Re:coded Outside the Coliseum, in Olympus Coliseum, is a good place to gain experience points. Walk towards the other end of the entrance and one Air Soldier, one Invisible, and two Wizards will spawn. After defeating them, more will appear. By defeating the multiple swarms of enemies, the player will gain around 8000 to 9000 experience points. Equipping Oathkeeper is recommended, due to its LV1 Clock Ability; Undo, which will protect the player from the Wizards', Air Soldier', and Invisible' status effect-based attacks and its LV4 Clock Ability EXP Boost; which provide an addition boost in experience points.

Kingdom Hearts Dream Drop Distance
With EXP boost equipped, go outside the tower in Symphony of Sorcery. Use Sacrifice until your HP bar is beeping. Then, use Meteor and Mega Flare to take out the Dream Eaters quickly. Go back inside the tower, and then back outside so the Dream Eaters can respawn. If your HP goes up past the alarm zone again, use Sacrifice again. You need health in the alarm zone and avoid having Spirits that have Cure spells so that EXP boost will work.