Here is the full list of all 28 Rocketbirds 2 Evolution achievements.
Complete all six chapters in Story Mode
As host, complete a rescue mission for all four locations in Rescue Mode
Unlock Hardboiled Chicken for Rescue Mode in the game
Find all 18 signs in all 6 chapters in Story Mode
Find 9 signs in any three chapters in Story Mode
Find all 3 signs of a single chapter in Story Mode
Kill all enemies during Hardboiled's final, successful escape in Chapter 6
Drop six Space Owls into the liquid ooze in Chapter 6
Defeat the swinging hexapod, once you see its health bar, in under 30 seconds in Chapter 5
Stand on the Hexapod's Nose while it is firing its missiles in Chapter 4
Detonate a bomb near either G-man in the final show-down in Chapter 2
Make enemies kill 15 co-workers in Chapter 2
Melee kill 15 Enemies in a row without triggering the alarm in Chapter 2
Headshot kill 15 enemies in a row in Chapter 1
Get someone to tell you what's up ahead in Chapter 1
Make Putzki shoot himself in Chapter 1
Unlock 100 costume items or weapons in Rescue Mode
Attain 3 star scores for all four locations in Rescue Mode
Attain a 80% or higher accuracy score on a mission in Rescue Mode
As host, collect all nine artifacts in Rescue Mode
Unlock all 4 hostages in the UFO in Rescue Mode
Unlock all 4 hostages in Jungliana in Rescue Mode
Unlock all 4 hostages in Putzki's Pork Plant in Rescue Mode
Unlock all 4 hostages in Putzki's Castle in Rescue Mode
Spend more than 50,000 bucks in Rescue mode
Headshot kill 100 enemies in the game
Melee weapon kill 100 Enemies in the game
Kill 4 Enemies with a single grenade shot in the game