{{Atari}} released this isometric video game in 1983. The player uses a trackball and a jump button to control Bentley Bear as he collects gems along the paths of the castles. Wearing the magic hat allows Bentley to kill the WickedWitch, Berthilda. Her gem eaters are vulnerable only while they are eating. Bentley can jump over the trees to stun them for a short time. Other enemies cannot be killed, so Bentley must avoid them. Secret warps take Bentley to higher levels.

A level ends when all the gems are collected. If Bentley gets the last gem, the player gets bonus points. Unlike most video games of the time, ''Crystal Castles'' actually has an [[http://www.vgmuseum.com/end/arcade/c/crycas.htm ending]].
!!This game provides examples of:
* BearsAreBadNews: Inverted, as Bentley Bear is the hero of the game.
* EndlessGame: Averted. In the early 1980s, when most games just went on until the difficulty outdid the player or the game [[KillScreen went awry]], its inclusion of a proper ending was quite unusual.
* EverythingsWorseWithBees: If Bentley stands still too long, a swarm of bees will appear.
* ExtremeOmnivore: The Gem Eaters very much do ExactlyWhatItSaysOnTheTin.
* InvincibilityPowerUp: The Magic Hat makes Bentley invulnerable for a few seconds.
* IsometricProjection: Specifically, this game uses trimetric projection.
* SpeciesSurname
* SymbolSwearing: Die on your last life and Bentley shouts "#?!" before he rises off-screen.
* WarpZone: The first, third, and fifth levels have a secret warp that takes the player to the next odd-numbered level, triggered by jumping in a specific corner of the level, sometimes while wearing the Magic Hat.
* WhenTreesAttack: The Nasty Tree enemy.
* AWinnerIsYou