Here is the full list of all 48 Time Survivors achievements.
Kill 10 T-Rexes
Kill 96 Triceratops
Upgrade Shuriken to max level during a run
Survive 5 minutes with Ned
Reach Level 10 with Ned
Complete "The Dark Age" stage
Meet the Mortician
Use the Red Leech for more than 600 seconds in total
Recover 2000 Health Points by any means
Defeat 3 Cerberi in a single run
Upgrade Plasma Gun to max level during a run
Deal a total of 500.000 damage with any fire weapon
Reach Level 66 with Nik in any stage
Walk 20 Km
Upgrade Slingshot to max level during a run
Kill 1000 scarabs
Reach minute 14:40 in The Dark Age stage
Upgrade Telescope to maximum level
Use the Tesla Coil for more than 600 seconds in total
Find 3 Giga Magnets
Kill 222 Evil Priests
Meet your first huge monster dog, the Barghest
Death is the way
Play a run in the full "Time Survivors"
Upgrade Ice Orb to max level during a run
Defeat a total of 5000 enemies
Find 3 Magic Mushrooms
Get 5 Apples
Destroy 20 vases
Upgrade Amoeba to max level during a run
Survive 6 minutes with Claire
Get 300 gold
Kill 2023 enemies
50 Gold turns into 100. Buy upgrades at the Shop!
Reach Level 10 with any character
Reach Level 5 with any character
Deal a total of 1.000.000 damage with the Shuriken
Reach level 16 with Mulan in "The Stone Age" stage
Complete the Egypt Age stage
Complete "The Egypt Age" stage
Survive 20 minutes with Ned
Kill the flying Pyramid
Survive 20 minutes as Cleo
Reach 25% in the Meta progression
Reach 50% in the Meta progression
Reach 75% in the Meta progression
Reach 100% in the Meta progression
Reach minute 5:55 in The Ice Age stage