All these achievements here are bound to the storyline, so they are impossible to miss.

Space adventurer
Finishing the outside of the Nahirg’s planet level.


As if you owned the place
Completing the Nahirg's base levels.


Spider killer
Finishing the cave levels.


This is getting hot
Finishing the rock and lava cave level.


Nothing can stop me
Finish the game.


NOTE: "Nothing can stop me" is a bit bugged. When the achievement doesn't unlocks after defeating the last boss, restart the last level and it should popup directly.

Frisbee player
Killing 100 enemies with the blade launcher.


This is in regular mode: just press X (on Xbox controller) or Q on keyboard and kill 100 enemies from a distance.

You can’t scare me
Killing a Nahirg general using only the blade launcher.


This is in regular mode: just press X (on Xbox controller) or Q on keyboard and kill a Nahirg general (the big one with a red suit) on distance and don't use any other attack.

Toaster
Kill 100 enemies using the flame thrower.


This is fire mode: just press X (on Xbox controller) or Q on keyboard and kill 100 enemies.

Ice cream man
Use frozen air to freeze 50 enemies.


This is ice mode: just press X (on Xbox controller) or Q on keyboard and freeze 50 enemies.

Avalanche!
Use rock spikes to kill 50 enemies.


This is rock mode: just press B (on Xbox controller) or W on keyboard and kill 50 enemies.

Rocky
Use the power of your rock punch to kill 50 enemies.


This is rock mode: just press X (on Xbox controller) or Q on keyboard and kill 50 enemies.

Variety is the spice of life
Kill 50 enemies using each of Zack’s powers.


This one should unlock automatically when you done the achievements above.

I feel the power
Reach Zack's suit level 20.


This one is easier then it looks like. Just make sure you look at every edge, pickup all green spheres and the little jumping monsters when you kill a enemy. Also you will get a bonus at each end of a level which will increase your suit level too.

Treasure finder
Find 5 nahirg treasures.


See achievement below.

Archaeologist
Finding all Nahirg treasures.


The game has a total of 39 Nahirg treasures.

NOTE: "Archaeologist" is a bit bugged. When the achievement doesn't unlocks after picking up the last one, restart the last level (or the level were u picked the last one up) and pick all the nahirg treasures up in that level again and it should popup.

Best way to show this is by a video. NOTE: This isn't my video.

Originally posted by Joshua Raposa:

arriving at the planet @00:00
meeting the locals @00:38
cozy village @02:45
visiting their home @03:23
into the base @04:47
going underground @06:39
little creatures @07:59
caught in a web @08:45
things heat up @10:57
on time? @12:42

Source: http://test-steamproxy.haloskins.io/sharedfiles/filedetails/?id=164073232