Full list of all 30 Halo: Spartan Assault achievements worth 1,000 gamerscore. It takes around 20-25 hours to unlock all of the achievements on Xbox One.
Complete all campaign mission specific Assault Ops
Earn all Gold stars in all operation missions
Earn 25000 XP throughout your career
Finish the objective without using any vehicles/turrets in Operation E, Mission 4
Complete Operation F, Mission 4 with the Blind and Thunderstorm Skulls active
Score a kill with every handheld weapon in the campaign
Complete Operation E, Mission 1 with the Hollow and Black Eye Skulls active
Complete Operation F
Destroy all Mega Turrets with the Grizzly tank in Operation F, Mission 2
Complete Operation E
Complete Operation D
Finish the objectives using only the Brute Shot, melee and grenades in Operation D, Mission 1
Get a higher individual score than your partner on all co-op missions
Kill a convoy target with every stationary gun in Operation C, Mission 3
Complete Operation C
Earn all medals in the campaign at least once
Complete Operation B
Finish the mission without any Jackal regenerating its shield in Operation B, Mission 3
Use every ability in the campaign at least once
Earn all co-op medals at least once
Earn all Gold stars in all co-op missions
Kill 10,000 enemies in co-op
Complete any campaign mission with the maximum number of Skulls active
Complete all co-op missions
Finish a co-op mission without becoming infected
Complete a co-op mission with at least 5 different players
Complete Operation A
Keep all Wolverines intact in Operation A, Mission 3
Earn your first Gold star in an operation mission
Earn a star of any type in an operation mission