Complete 3 challenges in the B.R.U.T.E. Squad Limited Time Mission to access the hidden star of this first week of challenges of season X.
Indeed, after having done 3 missions you will unlock a slightly different version of the B.R.U.T.E. loading screen. On this version 4 coordinates are written on the table behind which the character is hiding.
Following these coordinates, you arrive to the north of the map, at the umbrella shape quarry.
As usual, all you have to do is find the place indicated on the ground by a square of brown earth in the middle of the grass.There you go, the star is yours!
You can still pick it up after the missions have disappeared, as long as you have unlocked the secret loading screen.