Black's Mana Drain

[Xenophon]

Envelope Soul

1BB
Instant
Choose a Non-Creature, non-land card out of target opponent's hand.  That player discards that card.  At the beginning of your next upkeep, add that card's converted mana cost to your mana pool.

Too powerful?  What do you think?

[rvs]

It's kind of strange as an instant, seeing as all black discard is sorcery speed. I like the idea though, and I think it's costed just about right.

[Xenophon]

Yes, perhaps it should be a sorcery.  I upped the cost from Mana Drain jsut because I think it's a better card.  Active vs. Passive

[Marco]

If it's a black Mana Drain, why do you get the mana at the beginning of your upkeep? That can't be as useful as getting the mana at the beginning of your main phase.

I would have it look like this:

Envelope Soul
1BB
Sorcery
Target opponent reveals his or her hand. Choose a noncreature, nonland card from it. That player discards that card. At the beginning of your next main phase, add X to your mana pool, where X is that card's converted mana cost.

While I like the name, perhaps a name change is in order. Can you envelope the soul of a noncreature card? Or perhaps change it to "Choose a nonland card..."?

[Xenophon]

The name springs from the same routes as "Mana Drain."  While Drain allows you to drain the mana of a spell, envelope soul is allowing you to take a little energy of your opponent's mind (their hand)

So perhaps "Envelope Thoughts"

[Jacob Orlove]

Envelop Soul sounds like you're taking the energy from a creature.

Discard definitely needs to be sorcery speed. This still seems really good, because it can give you tons of extra mana early, whereas drain is at least limited by what they can cast.