Here is the full list of all 35 Neon Abyss achievements.
Complete a run without picking up any hearts.
Jump in the air for 10 times before landing.
Successfully hatch eggs 5 times in a row.
Get 50 eggs in a single run.
Jumped 9999 times.
Get killed by your bombs.
Defeat God of Violence.
Found 5 secret rooms in a row.
Defeat Goddess of Illusion.
Acquire 10 shields in a single run.
Fished 10 times in fishing room.
Completes the Piano challenge 10 times.
Acquire 10 heart containers in a single run.
Defeat the God of Electricity.
Death is another beginning.
Defeat God of Machines.
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.
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.
Made deals with Smirk Co. 99 times.
Played the Roulette machine 99 times.
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.