Book: Vex Axis Minds.
The Vanguard's intelligence sources now believe, with good confidence, that Sekrion oversees the expansion of the Vex network through the crust of Venus.
The Hydra chassis common to many Vex Axis Minds boasts impressive computational capacity. Sekrion likely uses this capacity to regulate coordination and crosstalk between Minotaurs operating in the construction role.
Destroying Sekrion should significantly hamper the Vex effort to incorporate the entire planet into their network.