Crystal Beast Deck

Overview
Every Crystal Beast deck will include some (but not necessarily all) of the following monsters:
 * Crystal Beast Cobalt Eagle
 * Crystal Beast Amethyst Cat
 * Crystal Beast Topaz Tiger
 * Crystal Beast Ruby Carbuncle
 * Crystal Beast Amber Mammoth
 * Crystal Beast Sapphire Pegasus
 * Crystal Beast Emerald Tortoise

Crystal Beasts also have many support cards to go with and aid any strategy the duelist using them may have in mind. They are as follows:
 * Rainbow Dragon
 * Ancient City - Rainbow Ruins
 * Crystal Abundance
 * Crystal Blessing
 * Crystal Beacon
 * Crystal Release
 * Crystal Tree
 * Crystal Promise
 * Rare Value
 * Crystal Raigeki
 * Crystal Pair
 * Crystal Counter
 * Last Resort (Ancient City - Rainbow Ruins support)
 * Rainbow Gravity (Rainbow Dragon and Rainbow Dark Dragon support)
 * Rainbow Path (Rainbow Dragon support)

Because of Crystal Beast's universal effect of transferring to the Spell & Trap Card Zone as Continuous Spell Cards when destroyed, some decks will also use cards that are influenced by Continuous Spells. Magna-Slash Dragon, Seismic Crasher, Gravi-Crush Dragon, Hamon, Lord of Striking Thunder, and Dweller in the Depths are examples of this type of Crystal Beast manipulation. The monster Rescue Cat is also an invaluable tool. With its effect, you can Special Summon Crystal Beast Amethyst Cat from the deck with ease.

Rainbow Dragon
Rainbow Dragon is a powerful asset to a Crystal Beast deck, and if you play your cards right it can be fairly easy to summon. If you decide to focus on Rainbow Dragon, be sure to add cards like Rainbow Gravity, Rainbow Path, Crystal Pair and Crystal Tree. These four are more useful in a Rainbow Dragon deck, so it's not recommended to add them to any other Crystal Beast decks. Also, it is possible to use Magical Merchant, in conjunction with Monster Reincarnation/Rainbow Gravity, to get Rainbow Dragon out of the deck, and the Crystal Beasts needed to summon it into the graveyard. Have three copies of Crystal Beast Sapphire Pegasus and Crystal Beast Ruby Carbuncle at your disposal, and two copies of the others to maximize the probability of summoning Rainbow Dragon. You can also use Lightsworn monsters as a boost and speed accelator, and benefit from their efects to send Crystal Beast monsters to the graveyard more quickly. Also 1 or 2 copies of Monster Reincarnation is very suitable to get Rainbow back to your hand.

Crystal Abundance OTK
The OTK is more competitively friendly. It utilizes Crystal Abundance's effect to work, so a few copies of the card is essential to have in the deck, as well as a way to search it out (Different Dimension Capsule or Gold Sarcophagus work nicely). There must be four Crystal Beasts in the Spell & Trap Zone, plus an open slot to activate Crystal Abundance. Wait until you have five Crystal Beasts on the field or in your graveyard with attacks of 1600 or more to activate the card. Upon activating Crystal Abundance, if your opponent had at least five cards on his/her field, all five of your monsters can be Special Summoned. Crystal Abundance leaves your opponent open to a direct attack.

Aggressive Crystal Beasts
This deck is a very weak build that relies on either depleting your opponent's life points fast, or destroying your opponent's cards fast. If you plan to burn through your opponent's life points, Seismic Crasher and Gem Flash Energy are good cards to include. If card destruction is your goal, then you should use cards like Magna-Slash Dragon, Gravi-Crush Dragon and Crystal Raigeki. Also, Dweller in the Depths and Hamon, Lord of Striking Thunder are general beatsticks for delivering the final strike, and Ancient City - Rainbow Ruins is a strong defensive card that doesn't take up a Spell and Trap Card Zone slot, so they are good assets. For both of the above strategies, it is absolutely essential to keep the number of Crystal Beasts in your Spell and Trap Card Zone high, so some common cards are Kuraz the Light Monarch, Crystal Beast Sapphire Pegasus, Crystal Blessing, Crystal Tree and Crystal Counter. There is another build of Aggressive Crystal Beasts known as Crystal Monarch. Working similiar to apprentice monarch, and using the Crystal Abundance engine, it's possible to beat your opponent down with the crystal beasts and then activate Abundance to clear the field, summon the CB's and then either before you attack or after, you can summon a Monarch for an added threat. As of right now, Crystal Monarch is the only stable aggressive build.

Synchro-Crystal Beasts
With the release of X-Saber Airbellum in the Starter Deck 2009, Crystals Beasts can become greatly competitive. The deck uses Rescue Cat to special summon Crystal Beast Amethyst Cat and X-Saber Airbellum to synchro summon for high-attack power level 6 syncrho monsters like Goyo Guardian. Also use Crystal Blessing, Ancient City - Rainbow Ruins in 3's for swarm and faster synchros. Or instead of the Rescue-Airbellum synchro engine, you could use Summoner Monk and level 4 tuners like Rose, Warrior of Revenge and abuse level 8 synchros.

Crystal Merchant
The focus of this deck is similar to Rainbow Dark Dragon Turbo. Fill your deck up with 3 Rainbow Dragon, 3 of each of the Crystal Beasts and a some Lightsworns monsters, as well as Magical Merchant and 1 Monster Reincarnation and possibly Heavy Storm. Use Magical Merchant to send Crystal beasts from your deck to the Graveyard. Then use Monster Reincarnation to get Rainbow Dragon to your hand. If you have it in your hand use Heavy Storm to clear your opponent of spells. Then attack with Rainbow Dragon. It's up to you about it's effect. The Lightsworns and Card Trooper can be used to send cards from your deck to the grave to help you get cards into your grave if you can't seem to draw Magical Merchant.

Monsters

 * Rainbow Dragon
 * Crystal Beast Ruby Carbuncle
 * Crystal Beast Topaz Tiger
 * Crystal Beast Amber Mammoth
 * Crystal Beast Sapphire Pegasus
 * Crystal Beast Amethyst Cat
 * Crystal Beast Emerald Tortoise
 * Crystal Beast Cobalt Eagle
 * Earthbound Immortal Aslla piscu or Earthbound Immortal Ccapac Apu
 * Rescue Cat
 * X-Saber Airbellum
 * Breaker the Magical Warrior

Spells

 * Ancient City - Rainbow Ruins -- This is a must-have in a crystal beast deck
 * Crystal Abundance
 * Crystal Blessing
 * Crystal Beacon
 * Crystal Release
 * Crystal Promise
 * Rare Value
 * Monster Reborn
 * Lightning Vortex
 * Crystal Tree
 * Giant Trunade -- this card will return the crystal beasts to your hand
 * Monster Reborn

Traps

 * Rainbow Gravity
 * Mirror Force
 * Torrential Tribute