Seto Kaiba and Sera ' s Duel Seto Kaiba and Sera faced each other in a game of " Duel Monsters " , in the Duel Links world . The Duel took place , as Kaiba attempted to ascend to the netherworld to face Atem . Sera warned him of the dangers and imposed a Duel in an attempt to stop him . Events . Prior . Kaiba set up the Duel Links virtual world , where he gathered Duelists ' consciousness via Neurons . He intended to rule this world as king . He hoped that assembling high levels of consciousness would enable access to other dimensions , including the netherworld , where he could face Atem . Sera was aware of these intentions and approached Kaiba at his house . She claimed to have heard the voice of an important person , residing in the netherworld , while in the Duel Links world . She began to suggest that Kaiba could do something by syncing with this superior consciousness , but disappeared just before Kaiba received word of unusual activity in the Duel Links . Mokuba Kaiba informed Kaiba of unfamiliar data registering on their main branch laboratory ' s Duel Links surveillance monitor . He showed Kaiba how test subjects ' Neurons signals were following an abnormal pattern and being drawn towards an unknown consciousness . Kaiba recognized this as the dimensional ascension he had been looking for and logged into Duel Links via his VR pod , much to Mokuba ' s concern . Inside Duel Links , Kaiba flew his " Blue - Eyes White Dragon " - themed jet towards the higher - level dimension , where Atem was . However , Sera , masked by her avatar flew next to him . She warned him of the danger he was approaching and asked if he was prepared to face a world of evil , transcending the boundaries of mortal man . Kaiba asked if she was questioning if he had fear in his actions and warned her that anyone who stood in his way would be mercilessly eliminated . She offered to let him proceed if he could defeat her , the holder of the superior consciousness , in a Duel and warned that he would die if he lost . Kaiba replied that this was interesting and accepted . Duel . Sera Summoned " Duza , the Meteoricubic Vessel " , which had 8800 Pulse ATK . Kaiba Summoned " Blue - Eyes White Dragon " , which had 3000 Pulse ATK . " Duza " attacked " Blue - Eyes " and Sera thought she had easily defeated it . However Kaiba offered one piece of criticism in Sera ' s lack of consideration and suggested that she might still be a child , who needs to learn how to better control her consciousness . The ATK of " Blue - Eyes White Dragon " rose to 5900 Pulse , due to Kaiba controlling his though frequency and then to 19900 Pulse . " Blue - Eyes " destroy ed " Duza " , reducing Sera ' s Life Points to 0 , causing her to lose . Aftermath . The design of Sera ' s avatar faded away , leaving her assume her regular form . She was slightly upset over losing an avatar she had been fond of . Having been defeated , Sera ceased efforts of trying to stop Kaiba and accompanied him , stating that there was no turning back now . Although they succeeded in approaching Atem , they were logged out of Duel Links , as Mokuba performed an emergency shutdown , as the amplified brainwave activity put Kaiba ' s life at risk . Aigami later spoke with Sera , saying that she was very close and that Seto Kaiba was not somebody they could easily eliminate . Cards used . Sera Kaiba