I made a deck focused around summoning Galaxy-Eyes Cipher Dragon to work with the new Cipher support at the time such as Galaxy-Eyes Cipher X Dragon, Double Exposure, and Cipher Biplane. (Link to Deck) However, the biggest issue the Deck had at the time was actually consistently drawing enough Cipher names in order to make your Rank 8 Cipher Dragons. Pot of Prosperity, while it would fix most of that issue, would cut your damage in half for the turn which is not what you want for a going-second deck. The new Horus cards, with each of them being an inherent summon from GY if you control Pharaonic Sarcophagus, are an incredible Rank 8 engine with their cards being able to easily send all 4 names to GY for enough material for 2 Rank 8 monsters without using your Normal Summon. This deck aims at going second in order to make Galaxy-Eyes Cipher Dragon and its compatriots to steal your opponent's monsters and overlay them into Cipher X Dragons to hopefully deal near-lethal damage to your opponent or prevent them from retaining resources on field and/or in GY.
For our monster handtraps, we have 2 Nibiru, the Primal Being, 3 Ash Blossom & Joyous Spring, and 3 Ghost Ogre & Snow Rabbit. For our Horus monsters, we have 3 Imsety, Glory of Horus, and 1 each of the rest: 1 Hapy, Vanguard of Horus, 1 Qebehsenuef, Aegis of Horus, and 1 Duamutef, Blessing of Horus. Functionally, we are only using them for a Rank 8 package, so their individual effects are irrelevant for the most part other than Imsety who can send itself and a card from hand to search Pharaonic Sarcophagus to get everything started. You will brick on Horus monsters if you play more than 1 of the other names. For Ciphers, we are playing 3 Cipher Biplane, 3 Cipher Twin Raptor, 1 Cipher Mirror Knight, and 3 Cipher Etranger. Biplane summons itself if another Cipher is Summoned and it can make 2 Ciphers become Level 8. Raptor is a free summon if your opponent controls a monster summoned from the Extra Deck, and it can discard 1 to summon a Cipher, preferrably Biplane, from Deck. Mirror Knight is just here as discard fodder since it searches a Cipher card during the End Phase of the turn it was sent to the GY. The same goes for Etranger, but it immediately searches a Cipher Spell/Trap when sent to the GY and it can attach itself from hand or GY to a Cipher Xyz Monster.
For Spell/Traps, we have 3 Pharaonic Sarcophagus which allows you to send a card from hand to send a Horus monster from Deck to GY up to 4 times per turn. Just sending all of the names in a turn gives you a repeatable, recurring Rank 8 package as long as Sarcophagus remains on field. 2 Triple Tactics Thrust and 1 Triple Tactics Talent. 3 Forbidden Droplet. 1 Rank-Up-Magic Cipher Ascension which is a fun little thing you can do. This ranks up Galaxy-Eyes Cipher Dragon into Neo Galaxy-Eyes Cipher Dragon to steal up to 3 monsters instead of 1. 3 Forbidden Chalice and 3 Infinite Impermanence because we are going all into this going second thing.
For the Extra Deck: 1 Divine Arsenal AA-ZEUS - Sky Thunder, 3 Galaxy-Eyes Cipher X Dragon because it recycles and/or summons back your Dragon Xyz Monsters and you can overlay into it using a monster you stole off of a Cipher Dragon because they are treated as Galaxy-Eyes Cipher Dragon when you do. 1 Galaxy-Eyes Cipher Blade Dragon which is targeted destruction. 1 Galaxy-Eyes Full armor Photon Dragon which is also targeted destruction. 3 Galaxy-Eyes Cipher Dragon as it is your main Rank 8 monster you are going into. 1 Number 90: Galaxy-Eyes Photon Lord as a monster negate to go into going first. 1 Hieratic Sun Dragon Overlord of Heliopolis which tributes monsters from hand and/or field to destroy cards. If you have an insufficient number of Ciphers in hand, but have all of the Horus monsters in GY already, your hand is just fodder for Heliopolis to destroy cards. 1 Number 38: Hope Harbinger Dragon Titanic Galaxy which is a Spell Negate going first. 1 Dingirsu, the Orcust of the Evening Star for removal and protection. 1 Divine Dragon Knight Felgrand for protection and/or a negate.
Side Deck isn't much. Some Levle 8 Kaijus, 1 Kurikara Divincarnate, 2 Lightning Storm, 1 Harpie's Feather Duster, 3 Forbidden Lance for going first or second for extra protection against Spell/Trap-based removal, the second Triple Tactics Talent, and 3 Solemn Strike for going first.