Infernoid Prediction Princess

Surely 3 Infernoid Decatron and 1 Infernoid Attondel make an Infernoid Deck. This is a bit of a wierd Deck. The strategy here is to Normal or Special Summon Infernoid Decatron in order to use its effect to send the Level 8 Infernoid Attondel from your Deck to the GY in order to make Decatron a Level 9, having it become a target on field for World Legacy Monstrosity. However, because you are essentially just playing 4 Infernoid monsters in the Main Deck to get you to a Level 9, there leaves a lot of space for non-engine as well as leaving you a lot of space in the Extra Deck to play pretty much anything you want. The only downside to this Deck is drawing the 1 Attondel you play as you cannot send from hand with Decatron.

Main Deck: Starting with the Infernoids, 3 Infernoid Decatron and 1 Infernoid Attondel. If Decatron is Normal or Special Summoned, you can send an Infernoid from your Deck to the grave in order to increase Decatron's Level by the Level of the sent monster and replace its name and effects with that monster's name and effects. Since we need to make Decatron a Level 9, we are going to be sending the Level 8 Attondel. Something to note about the Infernoids (excluding Decatron) is that they MUST be Special Summoned by their own effects and cannot be Special Summoned by other ways. There is a Level 9 Infernoid in Infernoid Devyaty, but since that Summoning requirement is slapped on it, we sadly cannot Monstrosity into it. Attondel requires you to banish 2 Infernoids from hand or grave to Summon it from hand or grave. It can attack twice if it destroys a monster by battle and can Tribute a monster to Quick Effect banish a card from your opponent's grave. Decatron inheriting Attondel's effect and it actually mattering rarely ever comes up, but either way, we are playing Attondel just to make Decatron a 9. For Prediction Princesses: 3 Prediction Princess Tarotrei, 1 Prediction Princess Tarotreith, and 3 Prediction Princess Bibliomuse. Tarotrei flips a monster face-up or face-down as a Quick Effect and Summons a Flip Monster face-up or face-down from your hand or GY during the End Phase. Tarotreith can be Summoned by the End Phase effect of Tarotrei and when flipped, it can Summon a Flip Monster from Deck face-down. Then, as a Quick Effect, it can flip any number of your monsters face-up or face-down. Bibliomuse adds a Prediction Princess and a Ritual Spell from Deck when flipped, it can Summon itself back face-down if it's Tributed, and it gives your Ritual Monster targeting and destruction protection against your opponent's effects. Go go alongside these, we are playing 2 Deus X-Krawler, 3 Spirit of the Fall Wind, and 3 Ash Blossom & Joyous Spring. In the situation where you do not draw Decatron, you can use your Normal Summon on Spirit of the Fall Wind. When Spirit of the Fall Wind is Normal Summoned, it adds a Flip Monster from Deck to your hand. You may not see me playing it much in some other builds of Prediction Princess because it only triggers on Normal Summoning it, and most of my other builds of Prediction Princess have something you'd rather be using your Normal Summon on instead. However, Spirit is still an incredibly good card in Prediction Princess. It can add either Bibliomuse or Tarotreith to hand. In the case of Bibliomuse, it isn't searchable by anything in-archetype, so having a way to search it to have it in rotation for Ritual Summoning is very good. As for Tarotreith, having a piece of your Prediction Princess combo in hand early as possible means that you can focus on other plays later in the turn or not have to commit so much to adding pieces to your hand at a vital part in your combo, such as when you make Aggregator. 

For Spell/Traps: 1 One for One in order to get Decatron on field. 3 Pot of Prosperity. 2 Pre-Preparation of Rites. We have a lot of space in this Deck for other cards because our Infernoid part of the Deck is literally just 4 cards in addition to the One for One. In that case, we can play Pre-Prep to have a more consistent way of accessing Tarotrei and a Ritual Spell. 1 Triple Tactics Thrust and 2 Triple Tactics Talent as a way to continue your plays or at least try to prevent your opponent from starting their plays if you are interrupted during your turn. 1 Prediction Ritual and 3 Underworld Ritual of Prediction. We are playing only the 1 Prediction Ritual as a search off of Pre-Prep. Having more than 1 copy in Deck means that you are basically boned if you draw 2 of it. Relying on Pre-Prep to get it from Deck gives you much more resources as it gets you both Prediction Ritual and Tarotrei. Underworld Ritual Ritual Summons a Prediction Princess from hand or GY face-up or face-down and can banish itself from GY during the Standby Phase to Summon a non-Ritual Prediction Princess from Deck face-down. 1 Called by the Grave. 1 Crossout Designator. 3 World Legacy Monstrosity. 3 Infinite Impermanence. For the sake of Monstrosity, you could play another Level 9 in something like Gizmek Kaku, the Supreme Shinng Sky Stag or Pot of the Forbidden in order to be able to get 2 Level 9's from Deck if you target Tarotrei in a situation where you have your Ritual pieces but not Decatron. Void Feast is a very tempting card to play as it gets you Infernoids from Deck on your opponent's turn with one of them being Decatron as long as their Levels equal exactly 8 with Decatron being able to send something like Infernoid Devyaty or Infernoid Onuncu from Deck to copy its effect for a Monster or Spell/Trap negate. However, there are 2 issues with that. 1) You need to play Void cards other than Void Feast in order to meet its activation requirement of having to send a Void Spell/Trap from hand or face-up field to activate.There are no Void Spell/Traps that work well in this Deck. Into the Void is bad because you want to keep your cards and resources in hand and having to discard your entire hand is something you don't want to do. Void Apocalypse and Void Imagination functionally do nothing in this Deck. And Void Vanishment, while it is good as it can discard a card to add a Void Spell/Trap like Void Feast from Deck to hand, it locks you into Infernoids for the rest of the turn. Sure, you can activate it at the end of your combo to avoid that, but it brings us to our next issue with Feast. 2) You need to play more Infernoids. Infernoids have to be Special Summoned by their own effect. And while Void Feast ignores those conditions, you are stuck with monsters that you literally cannot do anything with if you draw them. Maybe playing 1 more Infernoid name in Onuncu or Devyaty is fine in order to have access to a Spell/Trap or monster negate, but playing more names that don't do anything on their own and are not able to hard summon in this Deck will only make the Deck more bricky.

For the Extra Deck: 1 Baronne de Fleur. If you didn't know that Decatron is a Tuner, now you know. If you already have access to your Prediction Princess combo, or if you have another way to access Decatron like One for One, you can use it as a Level 1 Tuner to go into Baronne. Another Level 10 Synchro you could play is Masterflare Hyperion which can send something like The Executor of the Underoworld - Pluto or Protector of the Agents - Moon to copy their effect for a book or pop. And it can also banish a Fairy from hand or GY when your opponent activates a card or effect to banish a card on field. 2 Herald of the Arc Light for Ritual searches when sent with Aggregator. 1 Divine Arsenal AA-ZEUS - Sky Thunder, 1 Stellar Nemesis T-PHON - Doomsday Star, and 1 Infinitrack Earth Slicer. 2 Mereologic Aggregator which sends a monster from Extra Deck on Xyz Summon and can also reattach a monster from GY. You can send Herald for a Ritual search, reattach it, and Link off Aggregator for another search. 1 Jormungandr, Generaider Boss of Eternity and 1 Laevateinn, Generaider Boss of Shadows. 1 Underworld Goddess of the Closed World, 1 Knightmare Unicorn, 1 I:P Masquerena, and 1 Gravity Controller.

For the Side Deck: 1 Infernoid Devyaty and 1 Infernoid Onuncu. If you really wanted to, you could side 1 of them in to allow Decatron to send it and copy its effects for a Monster negate or a Spell/Trap negate. It's not exactly optimal, but it is definitely something you could do. 3 Thunder King, the Lightningstrike Kaiju, 3 Dark Ruler No More, 1 Harpie's Feather Duster, 3 Cosmic Cyclone, and 3 Evenly Matched.