Ax Crazy/Playing With

Basic Trope: An insane character is violent and a clear threat to others.

Straight:
- Edward is obviously nuts and runs towards Roger swinging a large shard of glass.
Exaggerated:
- Edward spends all day doing nothing but sharpening his knives and singing sinister versions of nursery rhymes.
- Omnicidal Maniac
Justified:
- Edward was intentionally shaped into a homicidal maniac by the Complete Monster cult that raised him.
- Or is an Artificial Human whose mind was corrupted during his conception.
- Or he's just a psychopath.
- Or he's completely insane and doesn't have restraints
Inverted: Edward's insanity makes him meek and ineffectual to an unhealthy degree.
Subverted: The insane Edward runs towards Roger swinging a large shard of glass; Roger prepares for the worst when suddenly Edward holds the shard out and asks Roger to please clean Mr. Shimmers for him.
Double Subverted: ...and as soon as Roger is distracted, Edward takes out some piano wire and proceeds to murder him horribly.
Parodied: Somebody calls Edward "Mr. Poopypants". He proceeds to grab an axe and kill everyone within a five-mile radius in an extremely over-the-top manner, screaming "Heeeeeeeeere's Eddie!"
Deconstructed:
- Edward suffers from a genetic disorder that causes frequent hallucinations, bringing back memories of his traumatic, abusive childhood; he reacts violently, striking down anyone in his path and believing it all to be in self-defense.
- His sociopathic elements do not stem from genetic issues or a Freudian Excuse; it stems from his raw determination to do whatever it takes to achieve a goal. However, others fear the fact that this person is really Not So Different from themselves; thus, they call him "insane" as a way to make it more "acceptable" to kill him.
- Under the mentality that Insane Equals Violent, the public ostracizes anyone with a psychological disorder as they believe "psychological disorder" automatically means "insane serial killer in waiting." This deprives the individual of crucial social support that would help him/her recover from or cope with the disorder.
Reconstructed: Edward realizes his problem and isolates himself from society, unwilling to face the consequences should he go berserk in the middle of a crowd.
Zig Zagged: Edward frequently needs to take meds to keep himself stable. Thanks to Rule of Funny and/or Negative Continuity, what exactly the pills do varies wildly from episode to episode; in episode 3 he was merely annoying without them, but in episode 56 he forgot to take them and subsequently attempted to murder Roger.
Averted:
- Edward's insanity does not have any significant impact on how violent he is, or Edward is not insane at all.
- Edward is a Complete Monster, but is full aware of what horrid actions he's doing.
Enforced: Edward's ax-craziness, combined with his good looks, is meant to appeal to a certain viewer demographic.
Lampshaded: "Woah, Edward, you're looking pretty creepy holding that shard of glass. You're not going to murder me in a bloody and incredibly painful manner, are you?" Cue Gory Discretion Shot.
Invoked: The irredeemably assholish Big Bad that Edward owes his life to attempts to drive him insane in order to make him a more efficient killer for The Empire.
Defied: "Edward, I think it's time for you to talk to a psychiatrist."
Discussed: "I don't trust that Edward. Sure, he acts nice and all, but he just seems like a ticking time bomb..."
Conversed: "In a horror story, right now would probably be the part where Edward has a mental breakdown and murders everyone graphically. Good thing we're not fictional characters, right?"
Played For Laughs: Once an Episode, Edward escapes from the asylum and attempts to murder Roger in increasingly flashy and ridiculous ways. Due to some trick of fate, Roger somehow manages to escape unscathed and none the wiser every time, and Edward is promptly captured and thrown back in the loony bin.
Played For Drama: To protect the people that he loves, Edward attempts to control his homicidal impulses, but his will grows weaker with each passing day...

Come with me to Ax Crazy. I'd like you to meet my best friend, Mr. Knifey...