Here is the full list of all 23 Zenohell achievements.
Clear the game with G90 (Continues allowed)
Clear the game with DRX-L (Continues allowed)
Clear the game with EON (Continues allowed)
Clear the game with XOP Ultra (Continues allowed)
Clear the game with G85 (Continues allowed)
Clear the game with Eonis Crystal (Continues allowed)
Clear ARC mode (Continues allowed)
Clear KAI mode (Continues allowed)
Clear ZOR mode (Continues allowed)
You started the fight of your life! (Stage 1 Clear)
Your home city was already in ruins when you arrived. (Stage 2 Clear)
You destroyed the alien nuclear warmachine. (Stage 3 Clear)
The angry robot was no match for you. (Stage 4 Clear)
It was even more shiny when it exploded! (Stage 5 Midboss Clear)
The harder they fall! (Stage 5 Clear)
everything before this, never mattered. (Stage 6 Boss Rush Reached)
You destroyed the multi-armament space station! (Stage 6 Clear)
You killed the Zenonian Overlord!! (Stage 7 Clear)
You chose to turn back
You will DIE!
You are a shooting star.
You are one among the elite of aces!
You defeated the nasty boss rush mode!