Well I saw this game somewhere else, and it wasn't here so you know sharing is caring!
The way this game works is very simple.
The letter 'A' will start the game, and the objective is to name a Yu-Gi-Oh card that starts with the letter 'A'.
Example:
Allure of Darkness
After that then we will go down the alphabet from A-Z so the next poster has to post a card that starts with the letter B.
Example:
Black Whirlwind
This will go on until we reach the letter Z, and once the letter Z is reached we will go backwards from Z-A and so on until we get bored of this game I'll start with the letter A
A - Aqua Dragon