Maybe Parasyte -the maxim-.
Death note , akagi , kaiji , one outs , paranoia agent
Steins;Gate
The Perfect Insider
Code Geass
Monster
Take a look at these
Psycho Pass
Stein's; Gate
The Promised Neverland
Re: Zero
Death Note
Perfect Blue (M)
Ghost In The Shell
Paranoia Agent
Higurashi
Future Diary
Another
Death Note for sure! I don’t watch many suspense animes, but out of the ones I have watched, that one is by far the best.
Tokyo ghoul or angels of death are the best imo
Death note fs
A shorter one is erased
What do you think?