boss theme (phase one):
https://www.youtube.com/watch?v=9odB9sD58Pc
boss theme (final phase):
https://www.youtube.com/watch?v=l5c_OALkqec
In his first phase, he wears heavy armor and throws gas grenades at you that slowly do damage over time, in order to damage him, you have to focus on his chestplate until it eventually gets destroyed, afterwards, you can easily take him out by shooting his chest.
In his final phase, the entire room is filled up with smoke, and he has full-body armor that you cannot destroy, he is also considerably slower, he also starts to release toxic gas around himself that slowly damages you if you are in it's radius. In order to defeat him, you have to shoot the gas filter on his head, after it is destroyed, he begins to choke on the gas around him, and eventually dies.
