Here is the full list of all 32 ONRUSH achievements worth 1,000 gamerscore. It takes around 20-25 hours to unlock all of the achievements on Xbox One.
Maxed out your Superstar Rating
Performed a 'VOMIT COMET' action
Earned 50 'CHECKMATE!' medals
Collected 250 or more Gear Items
Earned 5 Ubertags
Superstar - Won the Founders' Trophy
Earned 100 Gold 'GAME TIME' Medals
Performed 1000 'NEAR ALLY' actions
Superstar - Unlocked 'Superstars'
Played 10 LOCKDOWN Matches
Personalised all 12 Characters
Personalised all 8 Classes
Featured in the player spotlight 10 times
Reached player level 30
Played 10 SWITCH Matches
Earned 50 'HUNTER' medals
Played 10 COUNTDOWN Matches
Superstar - Unlocked 'Snowbound'
Played 10 OVERDRIVE Matches
Reached player level 15
Superstar - Unlocked 'Starpower'
Earned 10 Crashtags
Superstar - Unlocked 'Regeneration'
Reached player level 5
Superstar - Unlocked 'Uprising'
Performed a 'CRUSHED!' Takedown
Superstar - Started 'Origins'
Smashed 5 tombstones in a single match
Used RUSH for the first time
Taken down an opponent
Introduced yourself to the fodder
Used boost for the first time