This Deck is all about messing with your opponent. Step 1 is to get Nopenguin either on the field or in the Graveyard. He will be very important for later.
Then, if you draw an Aquarium Stage, you should totally activate it. Then set either Penguin Soldier or Nightmare Penguin face down. Their effects send cards from your opponent's field back to the hand. Except they don't, because the effect of Nopenguin will Special Summon itself from the GY, and then any effect that would cause a monster to return to the hand will banish it instead. Then, thanks to Aquarium Stage, your WATER attribute monsters won't be destroyed by battle.
If you're worried about some useless face-up penguins crowding up your field, don't worry. Book of Moon, Book of Eclipse or Ghostrick Doll can make sure they go back face down so you can use their effects again.
Once you've crippled your opponent's deck, you'll need to attack. That's why this deck had options. Tributing one monster will allow you to summon Great Emperor Penguin, which will allow you to Special Summon two other penguins. There are also plenty of Rank 3 and 4 Xyz monsters in the Extra Deck to use, though these can be swapped out with any you prefer. We just need something to attack with once we've banished all your opponent's important cards.
Royal Decree is also in this Deck, because most of the cards that would stop this strategy are Trap Cards, and we don't really need Trap Cards in this Deck anyway.
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