Ability Drain

Instant
Counter target activated ability. At the beginning of your next main phase, add

to your mana pool, where X is the amount of mana spent on that ability's activation cost.
Pretty straightforward. In the "new Mana Drain" thread, I got to thinking about how blue can't really do the "ritual" thing anymore, making a Mana Drain remake kind of sketchy from a color standpoint. But green can do rituals! And green can counter things (kinda)! So this seemed like an elegant, unexplored combination of those two abilities.
I believe that this templating is correct. Compare to Protective Sphere.
I recognize that the costing is pretty aggressive, but Bind cantrips instead of ramping mana, Bind sucks, and the mana is not that much better than a cantrip given how few activated abilities actually cost that much mana. If anything, you might even get away with this at

. I think that the card is cool and definitely worth printing, but I don't think it's all that playable.