Sergeant Zek

Sergeant Zek is a Grineer character first named by Cephalon Cordylon. He confronted Captain Vor when the latter reached Pluto to search for Tenno and attempt to scare him away, saying that the Tenno found there were his prize. Vor responded by attacking him with a Nervos, seemingly killing him. However, accordingly to Cordylon, Zek survived the encounter his military career was not for fortunate. The humiliation he endured in front of his fellow officers and his inability to show sufficient gains after the debacle that followed Vor's arrival caused him to be demoted. Zek was sent to outpost duty on Mercury, where injuries sustained at Vor's hands only continued to hamper his advancement.

Trivia

 * There is some confusion as to the identities of Sergeant Zek and Boril as they both effectively play the exact same role and exact same dialogue in both The Call trailer and the Tutorial before Starchart 2.0 while appearing on different planets. In a post-Devstream Trailer, the Queens order Vor to "take the Rail to Pluto" and that Boril is now in command, suggesting that Boril was the Grineer he encountered and assaulted in The Call.
 * However, As Boril's name is given via captions in the most recent, Earth-based iteration of the Tutorial (the Vor's Prize quest) is appears that Boril was encountered on Earth while Sergeant Zek was encountered on Pluto, where he might have been acting on Boril's behalf.