Here is the full list of all 22 Katana ZERO achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Achieve a total rank of gold or higher in a full speedrun.
Defeat the psychiatrist's final form.
Found all the hidden keys.
Didn't wake up Leon.
Found what the robber left behind.
Fulfilled your secondary goal in the prison.
You stopped a suicide. With a murder.
Your trap card was activated.
You ruined his fresh track suit.
Kill yourself in an elevator.
Jump off the balcony of the penthouse.
In 1962, the Orlons released one of the all-time greatest doo wop hits, Don't Hang Up. Google it. Anyway, you hung up your phone a lot.
Meet your final end in chinatown.
Complete a full run in hard mode.
Poor guy.
You really liked petting that cat.
Why did you think it was a good idea to give him your Katana anyway?
Beat Katana ZERO.
Complete The Dragon's tape.
You killed a suspiciously familiar character on the Quiet Hills set.
This will go well...
Most people go right. You went left.