Are you ever looking through cards and you see over and think, "Huh. Who made that?" I have no recollection of making this card.

Hee.

My first thought on seeing this: Some players might try to claim that, with two of these out, you get an infinite loop. This is a triggered ability, after all, and it's (indirectly) caused by a creature attacking or blocking...

My second thought: Wait, that doesn't actually need two, does it? If it worked that way, this would be a 1-card instant stall to the game.

When I find cards I made and forgot about, I normally think "Oh, that's a really good idea, but it's a bit too complicated" :)

And yes, I assumed (and assumed most players would assume) this only applied to direct triggers. I would guess that's ok in the rules but I'm not really sure.

I'm pretty sure the rules only look at direct causation for things like Hushwing Gryff.

The trigger for this is an ability triggering, not the attack that causes the ability to trigger, so I think it would be okay. I imagine it's sort of like replacement effects that don't affect themselves infinitely. I agree that this is confusing, though. I've played with people who don't really get regular triggered abilities, especially ones with payment — people who try to use Yasova Dragonclaw multiple times, for example— so I don't think this card would be very printable.