Oh, good idea. It's still situational, but stands a much higher chance of hitting a creature they cared about; if you're lucky one with protection from black.

I'm worried it looks a bit too white with this form of restriction, but it's a good place to start.

It is a white effect (Reprisal, Intrepid Hero, Radiant's Judgment, Topple), but black got it in Planar Chaos with Big Game Hunter. It looks fine to me.

That's an interesting take on it, yes. I don't think you'd want it on more than one or two cards.

I can't decide if I should incentivising Delve or if I should reward people who pay the full price.

I came to this design first just because of its similarity in function to Vendetta and the power of "destroy target creature" without any reservation. But I just don't know...

My instinct tells me that you should incentive full price. If a player pays delve to take less damage, then draws another, more important delve card, that player will be unhappy. I like stress in my design, but being forced to choose between two known things is not as frustrating as being forced to choose between an okay effect now, or a great effect that may never appear.

Note: the comments in this thread actually belong to (((Soul Corruption))).

I was going to suggest something like this, but was afraid of sounding contradictory in my comments. I like where this and Soul Corruption are now... they read much better.

Yes, I think this is a good pair of cards to have now.