Here is the full list of all 35 Neon Abyss achievements.
Defeat Goddess of Illusion.
Get 50 eggs in a single run.
Jump in the air for 10 times before landing.
Jumped 9999 times.
Complete a run without picking up any hearts.
Defeat God of Violence.
Defeat the God of Electricity.
Get killed by your bombs.
Defeat God of Machines.
Successfully hatch eggs 5 times in a row.
Acquire 10 shields in a single run.
Death is another beginning.
Defeat God of Darknet.
Failed to hatch eggs 5 times in a row.
Get killed by environment damage 9 times.
Unlock 6 Characters.
Died in the Abyss 99 times.
Found 99 secret rooms.
Acquire 10 heart containers in a single run.
Entered the abyss for the 999th times.
Unlock Abyssal difficulty.
Opened 999 locked chests.
Stepped on worms 999 times.
Get killed by your own bomb while in the air.
Completes the Piano challenge 10 times.
Fished 10 times in fishing room.
Made deals with Smirk Co. 99 times.
Played the Roulette machine 99 times.
Found 5 secret rooms in a row.
Defeat God of Machines without getting hurt.
Defeat Athena in Abyssal Difficulty.
Complete a run without losing any hearts.
Empty 4 shops in a single run.
Defeat Argus without picking up any items.
Dance in the bar for 30 minutes.