From Halopedia, the Halo wiki
The Tactician was relatively slight of build and younger than most other Forerunners of the same status — less than two thousand years old by 97,445 BCE — but his accomplishments during Mendicant Bias's initial revolt had gained him substantial recognition; the IsoDidact considered the Tactician so capable that he could very well be chosen in his place. He went into temporary retirement following the fall of Master Builder Faber, but returned in command in the final years of the Forerunner-Flood war. After most of the ecumene had fallen to the Flood, he gathered with the other Forerunner commanders at the greater Ark in an emergency conference. He objected to the Examiner's assertion that the Flood and the Precursors were one and the same, exclaiming that this was "doubtful in the extreme". This was echoed by the other commanders, as well as the IsoDidact, who agreed that the Flood were no longer the same as their creators. The Tactician was supposedly killed during the Flood's attack on the greater Ark.
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