Zero

Zero (ゼロ) is the main protagonist and player character of Death Game. He was a citizen of Terraria and descendant of the famous Legendary Knights, who was inexplicably chosen by "The One" to represent Terraria in a game of death. Zero befriends Omega and they put together a team to compete in the titular Death Game against other "players."

Leading the team, Zero battles various players across different dimensions, while also encountering the Chaos Agency, who want to kill The One. Eventually, while Zero and his team emerge victorious, Zero, Omega, and Theresa's teammates betray them and kill The One with the Spear of Destiny, causing the dimensional barrier to crack and unleash Xeno, who kills them instantly in a flash of light.

To date, Zero is the only protagonist to canonically die.