Here is the full list of all 24 Laser League achievements.
Unlock all other Achievements
Activate 5000 Laser Nodes (Online Play)
Reach Prestige rank 01
Revive 500 teammates (Online Play)
Reach Mastery rank 2 with all base game Classes
Reach level 20
Hit 3 or more opponents in a single Smash ability use (Online Play)
Shock 3 or more opponents in a single Shock ability use (Online Play)
Steal 4 or more Laser Lodes in a single Thief ability use (Online Play)
Teleslice 2 or more opponents in a single Snipe ability use (Online Play)
Finish a match with the highest revive streak 5 times (Online Play)
Traverse 4 or more opposing Lasers in a single Ghost ability use (Online Play)
Reach Mastery rank 5 as any Class
Eliminate 1000 opponents (Online Play)
Win 50 matches (Online Play)
Reach level 10
Finish a match as MVP 10 times (Online Play)
Eliminate 2 opponents with a single expanding Laser (Online Play)
Finish a match with the highest elimination streak 5 times (Online Play)
Level up for the first time
Slice 2 or more opponents in a single Blade ability use (Online Play)
Win a match (Online Play)
Win a match without the opposing team scoring a point (Online Play)
Complete the Tutorial