Here is the full list of all 18 Xenon Valkyrie achievements.
You Kill to AI MotherShip
You got his blessing
You left behind Blackstorm Lab
You Kill to Deftos
You got the best weapon
You got the legendary weapon
You raised the sword
You left behind Ivory Tundra
You fought to the end
You left behind Phoenix Wastes
You left behind Gilgacocoon
Fixed the Teleporters
You get an exemplary level
You left behind Prime Reactor
You helped Dook
You left behind Thule Wulz Grotto
You shopped at the store.
You left behind Acient Techforest