Goat Format Return deck, only this time with Fiends and primarily using Necrofear to dump things away. Return decks do struggle with balancing stuff you actually want to get rid of to benefit off the card while also making sure you don't brick, so this tries to balance a good few boss monsters with lots of consistency and destruction from everything else. Generally the deck is fine establishing field presence due to this.
Boss monsters include Ruler for the very handy effect negation and Skull Archfiend for targetting immunity. Paying 500 every turn doesn't matter when you're going to be either going for a big push with Return or just bashing into things; plus losing life points isn't a huge issue with Return decks anyway.
Spells include Book of Moon to recycle your Assailent/Mimics while also handling potential problem cards. Stuff like Card Destruction and Lightning Storm help run through your cards easier.
Traps are minimalistic given the heavy focus on monsters. Phoenix Wing helps as a cost card to speed things up while everything else acts as pure fundementals to clean the field if required or disrupt plays.
Side deck is a wide assortment of potential counters to builds, either going more field-focused with backrow to Brain Control as alt-removal to the typical Mind Control/Spy plays to handle metagaming if needed.
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