Here is the full list of all 18 DAMNOSAUR achievements.
Reached 1,000,000 points in a single run
Used the Revive 4 times in a single Co-Op run
Survive for 30 minutes in a single run
Defeat 250 Raptors
Defeat 100 Triceratopses
Defeat 100 Pterodactyls
Defeat 80 Lizards
Survived an encounter with an Armoured Triceratops
Survived an encounter with an Exploding Pterodactyl
Survived an encounter with a Scary Lizard
Survived an encounter with a B-Rex
Survived for 3 minutes without changing from the Pistol
Unlocked the Meteor Gun!