Of a person: intending or likely to commit murder; bloodthirsty, homicidal.
Very difficult.
Of an object: used to commit murder; capable of causing death; deadly, fatal.
Of, characterized by, or pertaining to murder or murderers.
Likely to commit, or to attempt to commit, suicide.
Extremely reckless.
Highly likely to certain to result in the deaths of the participants; dangerous or reckless to such a degree as to be tantamount to suicide for those taking part.
Pertaining to suicide.
Someone suicidal; someone likely to kill themselves.