You can get:

• 2 game codes for Legacy of the Duelist: Link Evolution
• A physical playmat with the Duel Links logo
• A Duel Links T-Shirt
• An Oversized Dark Magician (Dark Side of Dimensions artwork)

Event is limited to citizens of Washington D.C. and the 50 States of the USA.

For exact rules, please check here

For Social Media Pages

• Yu-Gi-Oh! TCG on Twitter
• Yu-Gi-Oh! TCG on Facebook
• Yu-Gi-Oh! Duel Links on Twitter
• Yu-Gi-Oh! Duel Links on Facebook
• Yu-Gi-Oh! Duel Links on Instagram

Source 1

Source 2