Here is the full list of all 19 Red Risk achievements.
Kill 2500 Infected.
Reach level 10.
Survive ten tournaments.
Reach level 9.
Kill 1000 Infected.
Reach level 8.
Survive five tournaments.
Reach level 7.
Stay alive for 5000 seconds.
Survive your first tournament.
Stay alive for 2500 seconds.
Reach level 6.
Stay alive for 1000 seconds.
Kill 100 Infected.
Reach level 5.
Reach level 4.
Reach level 3.
Reach level 2.
Enter the arena.