Poisoned Wells - Legendary Land

[Longshot1010]

<Tap>, Choose a mana color. Until the end of the turn each creature, land or artifact tapped for that color mana deals one damage for each mana drawn from it to its controller. Poisoned Wells' controller receives two poison counters.

[DatAsh]

This card just doesn't work the way you worded it. I'm not sure there is a way to word this correctly, it's a very poor design.

[Twanos]

I get where you're going... Maybe something like this...

<tap> Choose a color: Until end of turn, whenever a mana of the chosen color is added to a player's mana pool, Poisoned Wells deals 1 damage to that player. Add 2 poison counters to Poisoned Wells controller.

I tried to clean it up a bit, but it's still a bit clunky. I like the concept thought.