I had started thinking of lands that would have a recurring ability to sacrifice creatures as some kind of anti-Oath tech. For instance, a playable variant of Diamond Valley or City of Shadows. That just got me thinking about lands that sacrifice creatures, and I came up with this idea as the potential start of a cycle of "spell lands". These would be like Smoldering Spires et al. from Zendikar block, but with an effect you only get if you pay some cost. Here's the one that first came to mind:
Puddle of the Dead
Land
Puddle of the Dead enters the battlefield tapped.
When Puddle of the Dead enters the battlefield, you may sacrifice a creature. If you do, add
to your mana pool.
: Add
to your mana pool.
I'd personally be in favor of making it a Swamp, but it seems that R&D doesn't like to do that, so I didn't. Also, I know that black no longer gets fast mana effects, but I just liked the admittedly jokey flavor of Puddle of the Dead.
Current Wording:
Puddle of the Dead
Land
Puddle of the Dead enters the battlefield tapped.
When Puddle of the Dead enters the battlefield, you may sacrifice a creature. If you do, add to your mana pool.
: Add to your mana pool.
