I like this a lot, especially considering modern draft order, as this will take on radically different limited valuations once Morph is introduced into the format.

Not keen on creative side of things though. I love some alliteration, but I don't know what these abilities have to do with daggers.

Pretty fair assessment. How would you re-skin him in this setting?

Took a completely different turn with this guy. Lost the "plays well with morph" aspect, but I like the flavor he carries this way.

This is cool, but the flavor feels ripe for a Clue minigame:

Whenever another creature dies, name a card, then target player reveals his or her hand and discards a card with the chosen name if possible.

Wow. That becomes ridiculous with mass removal. It's also got nice synergy with the red Evidence trigger.

I like it.

Toyed with a "specter" build in which he became an "inspector". Decided that the pun just went too far.

To what limits can a pun go?

But wait, a new idea! What if there were two separate triggers:

Whenever a creature ETBs, target player puts the top card of their library into his or her graveyard.

Whenever a creature dies, exile target card from a graveyard.

First he has suspicions, and then he confiscates the evidence!

I think I'd prefer a build where he's not necessarily part of any conspiracy. Part of what makes Debronian vampires tick is that they've found ways to assimilate themselves into the society and culture. The Debronian Forensician is one example, and I feel like the Detective should follow suit. Ideally, this guy comes across as someone who doesn't give a damn about right or wrong, only about the letter of the law.

Which sounds like a white thing, now that I'm writing it, but I'm certain there's room in black for it. You know, Lawful Evil.

The biggest challenge I'm finding is using black to describe "fact finding" in a manner other than mill or discard. There's nothing strictly wrong with either of those methods, but if this guy is supposed to represent some angle of soulless law, I'd like to avoid lumping him with the Mindstrikers, who really are spies and thieves.

It’s an entirely new kind of take on black life gain, but I don’t think it’s that much of a stretch. Black gets lifelink, it has Abattoir Ghoul, it has (or had) Drain Life. This vampire effectively drains information.

This is the kind of “integrated vampire” I’ve been wanting to build. I feel like in the right society and under the right condition, there’s got to be situations where their abilities can be put to a productive use. They use their skills to their advantage, but aren’t necessarily (all) psycho-killers and criminals. They’re probably still cold and emotionless, but good at what they do.