Final Library

(Update-I: Added Dugares and Number 107 for better consistency. Now, you can find The World with Seventh Tachyon and discard it with Trade-In, if needed. Reason is that you can bring it back with Dugares rather than Knight.)

Hey there! In this deck, we will win with "Final Countdown" using "Royal Magical Library". You heard me right, as I have done it previously in Panda-Tethys-Junk decks. So, it should be easy.

Gameplan

1) Draw your whole deck with Library. You can find it with "Seventh Tachyon" thanks to Number 104.

2) With Double Summon + Pendulum Summon + Trismagistus, make sure you have 3 x Level 4 monsters. Then, XYZ Summon Knight or Dugares with these two and play Countdown + Barrier + Void.

3) Activate Knight or Dugares to bring forth The World and choose the outcome as heads with Barrier to skip your opponent's turn at the cost of sending two of your monsters you control to GY. These will be remaining Level 4 monster and Knight/Dugares.

4) With turn skipped via The World and Void sending your hand to the GY, you can summon Balerdroch + Cockroach forever for The World to skip turns until you win the duel with "Final Countdown".

If you wonder how to save up some SR and UR points, I can show you:

- "Spellbook of Secrets" + "Spellbook of Knowledge" + "Wonder Wand" can be collected by purchasing "Spellbook of Prophecy" deck. 90 SR + 30 UR saved and you can try a new deck!

- "Trade-In" can be collected by purchasing "Origin of the Galaxy" deck. 90 UR saved and you can try a new deck!

- "Seventh Tachyon" + "Number 107: Galaxy-Eyes Tachyon Dragon" can be found within "The Ultimate Sparkle" Timed Pack to save 60 UR!

- "Number 60: Dugares the Timeless" can be found within "Number Recall" Secret Pack to save 30 SR!

- "Chicken Game" can be found within "The Most Dangerous Race of the Cosmos!" Secret Pack to save 90 UR!

- "Performapal Monkeyboard" can be found within "The Bizarre Playing Board" Secret Pack to save 30 UR!

- "Doomking Balerdroch" can be found within "Abyssal Underworld!" Secret Pack to save 30 UR!

- "Arcana Force XXI - The World" + "Light Barrier" can be found within "Hand of Fate" Secret Packs to save 30 SR and 30 UR!

- "Into The Void" + "Allure of Darkness" can be found within "The Infinite Void" Secret Pack to save 180 SR!

- "Land Flipping" + "Final Countdown" can be found within "Legacy Pack" to save 60 UR!

So, in total, you can save up to 330 SR and 420 UR, if you are willing to spend some gems. Other SR and UR cards I didn't mention are essential.

That's all for this one. If you have any questions, feel free to ask. Have fun in Master Duel!