"Cyber End Dragon" and three "Cyber Dragons".
"Cyber Dragon" (サイバー・ドラゴン Saibā Doragon) is an archetype of cards that are also part of the "Cyber" archetype. They are a group of Machine-Type monsters, most of which are LIGHT, used by Zane Truesdale, then later by Syrus Truesdale in the Yu-Gi-Oh! GX anime and manga.
In the OCG, a Deck centered around this archetype was released in December 2013, Structure Deck: Blitzkrieg of the Mechlight Dragons, which will bring more members, support cards, and the brand new Xyz Monster "Cyber Dragon Nova".
"Chimeratech" monsters are related to, but not part of, the "Cyber Dragon" archetype, being composed of DARK, Machine-Type Fusion Monsters. Both "Chimeratechs" require multiple Fusion Material Monsters, one of which must be a "Cyber Dragon". The ATK and DEF of the "Chimeratechs" is a variable multiplied by the number of monsters used in its Fusion Summon, which can be as high as the user wants. The variables are x800 for "Chimeratech Overdragon" and x1000 for "Chimeratech Fortress Dragon".
The main strategy for these cards is to Summon the stronger "Cyber Dragon" Fusion Monsters. When building a Deck around these cards use strong Machine-Type monster cards to help keep the field clear and to unleash the devastating powers of the "Chimeratech" cards. Union Monsters, like "Heavy Mech Support Platform" and "Armored Cybern", can help with supporting monsters already on the field. The effect of "The Light - Hex-Sealed Fusion" can be used to Special Summon "Cyber Twin Dragon" and "Cyber End Dragon".
A quick way of swarming the field is by Special Summoning "Proto-Cyber Dragon" with "Photon Lead", then activating "Inferno Reckless Summon" and Special Summoning all "Cyber Dragons" from the hand, Deck and Graveyard, resulting in a massive field advantage and the ability to perform Xyz and/or Fusion Summons.
"Honest" is ideal to support the LIGHT monsters. "Jinzo" can negate all Trap Cards or "Cyber Phoenix" to negate Spells and Traps that target Machines on the field providing protection to Special Summon "Cyber Twin Dragon" without worrying about your opponent traps or spells, while providing more Fusion Material for the "Chimeratech" Dragons.
"Limiter Removal" can be used in place of an "Honest", as it affects all Machines, though with the fatal drawback of destroying all your Machines at the end of the turn. "DNA Surgery" is also a good card to include, since it allows you to use your opponent's monsters for "Chimeratech Fortress Dragon" ("DNA Surgery" + "Super Polymerization" for "Chimeratech Overdragon" is another option) as well as clearing your opponent's field for an easy OTK.
There are times when "Chimeratech Overdragon" can be removed from the field as soon as its Summoned by means of "Bottomless Trap Hole", "Solemn Warning", and "Torrential Tribute". When you have LIGHT Attribute Machine-Type Monsters on your field, they can also be used as Summon requirements for "Cyber Eltanin" by just banishing them. Not only will "Cyber Eltanin" have high ATK, but once its Summoned to the field it also clears it of any other monsters besides itself leaving your opponent open to a direct attack. A quick combo is to use the "Gadgets" to bring Machine-Types to your hand so you can fuse them with "Cyber Dragon" to create "Chimeratech Overdragon".
With the new cards that will come in Structure Deck: Blitzkrieg of the Mechlight Dragons, part of the Cyber Dragon's strategy will rely on swarming the Field and even managing the level of the "Cyber Dragons" for a quick Xyz Summon of their new ace card, "Cyber Dragon Nova".
"Transmodify" can be useful as it allows you to tribute a "Cyber Dragon Zwei"/"Cyber Dragon Drei" to Special Summon a "Cyber Dragon" from the Deck and perform the Xyz Summon of "Cyber Dragon Nova" if you have another "Cyber Dragon" out already.
You can combine "Cyber Network" with "Cyber Dragon Nova" to retrieve all "Cyber Dragons" banished by their effects and maintain a huge Field presence.
"Cyber Repair Plant" can be used to give fuel to "Cyber Dragon Nova" as it searches a "Cyber Dragon" for you to banish as cost for its effect, but can also be useful to perform the well-known Special Summon of "Cyber Dragon", if you control no monsters while your opponent does.
Another combo that can give speed to the new version of the Deck is "Foolish Burial" + "Cyber Dragon Core". Send "Cyber Dragon Core" from the Deck to the Graveyard and you will have conditions to quickly Special Summon a "Cyber Dragon" directly from the Deck. Another smart use for this monster, once it is treated as "Cyber Dragon" while on the field or in the Graveyard, is to banish it to boost "Cyber Dragon Nova"'s ATK, so this can be useful if its first effect were used and you don't want to let it exposed on the Field.
If you have "Cyber Dragon Core" on the field, "Machine Duplication" will Special Summon "Cyber Dragons" directly from the deck. This can lead to an immediate "Cyber Dragon Nova". Furthermore, with "Limiter Removal", you can have an 8400 ATK Monster when combined with "Nova"'s effect (by banishing "Core"). Or, instead of summoning Nova, if you have "Power Bond", you can use it to summon "Cyber End Dragon" with 8000 ATK.
The most common exploitable obvious countermeasures to this deck include System Down which can eliminate the presence of all machine type monsters on the field aswell as those in the graveyard (which the Cyber Dragon archetype are heavily reliant on as most monsters within it allow them to share it's name). Karma Cut has also been shown to be a very good counter measure to the deck as it can easily eliminate every monster that shares the name of Cyber Dragon and is more splashable against common deck types such as Zombie and Harpies. Another option is Electric Virus which while uncommon can allow the user to prevent a potential one turn kill from the common extra deck monsters within the deck.