Every Yugioh series is based on something that occured way back in the past. This one is no different, but it does it better. Vrains is all about setling things with the past. Lost Jiken is what gonna move not just the MC, but all the villains in the series. Playmaker, and Soulburner later too, seeks justice, Revolver seeks to attone the sins of his father. The second season brings some discussions about Artifical Inteligence and freewill, the importance of the limits of our free will. The last part of Vrains unite both and brings the meaning of life. Playmaker beliving in no absolute truth,but in the human bounds as the substance of life (what is true, but doesnt make sense at all). Ai seeks the ultimate meaning in life, "If there is no final answer, than is better not to live". Revolver belives in the ultimate meaning, the afterlife, and i belive that this is the meaning of the last scene.