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.
Complete a full run in hard mode.
Defeat the psychiatrist's final form.
This will go well...
Found all the hidden keys.
Found what the robber left behind.
Didn't wake up Leon.
Kill yourself in an elevator.
Your trap card was activated.
You ruined his fresh track suit.
You really liked petting that cat.
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.
Jump off the balcony of the penthouse.
You stopped a suicide. With a murder.
You killed a suspiciously familiar character on the Quiet Hills set.
Beat Katana ZERO.
Complete The Dragon's tape.
Meet your final end in chinatown.
Poor guy.
Why did you think it was a good idea to give him your Katana anyway?
Fulfilled your secondary goal in the prison.
Most people go right. You went left.