Question: when was gx added to duel links?
Answer: On September 28, 2017, GX World was added to the game, introducing many characters and cards from the Yu-Gi-Oh! GX anime series, as well as a focus on Fusion summoning. As of September 25, 2018, the 3.0 update added 5D'S world to the game, introducing characters and cards from the Yu-Gi-Oh!