This covers the final boss again, but this time with the ArFA-Sys charm that allows you to get the true ending. Here are the timestamps and notes.
Note: Once you are given the charm by ArFA-sys (like at the start of this video) then you are able to get the true ending.
0:00 Rei gives the player character an important charm
0:27 With the charm, get ready to fight the final charm. The choice between Zeliska and Kureha doesn't matter now.
0:51 Nervegear
1:08 Zeliska, Kureha, Itsuki, ArFA-sys, and the player character arrive.
8:41 A personal talk with Kureha.
11:08 The group make a plan for the fight.
14:07 The GM boss fight
15:54 This is the point things change. Kureha and Zeliska both survive regardless. Yui contacts ArFA-sys.
17:08 Kirito teleports in and informs everyone Death Gun is taken care of. Itsuki reveals he is the villain.
19:48 Everyone else teleports into the area.
20:56 Select the team for the final fight. You get special dialogue from people you pick
21:14 Judgement, the true final boss, is just a stronger version of The GM.
2:14 After the battle, Itsuki complements the player.
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