Delve & Taxing Effects

[Krasman]

Does anyone know how Delve cards interact with taxing effects such as Thorn of Amethyst or Sphere of Resistance?

Specifically I am wondering if you could just exile an additional card from your graveyard to pay.

From the Comprehensive Rules (Khans of Tarkir)
702.65. Delve 702.65a Delve is a static ability that functions while the spell with delve is on the stack. "Delve" means "For each generic mana in this spell’s total cost, you may exile a card from your graveyard rather than pay that mana." The delve ability isn’t an additional or alternative cost and applies only after the total cost of the spell with delve is determined.
702.65b Multiple instances of delve on the same spell are redundant.

[PirateKing]

Yes, total cost included taxes is determined, and then you pay, using mana or delved cards.

This doesn't operate under "counter spell unless it's controller pays x" cards like Daze or Nether Void

[Krasman]

Yes, total cost included taxes is determined, and then you pay, using mana or delved cards.

This doesn't operate under "counter spell unless it's controller pays x" cards like Daze or Nether Void

That is what I figured, I just wanted to make sure.

[cdr]

Avoiding Trinisphere with delve is fun.

[Dice_Box]

Avoiding Trinisphere with delve is fun.

There is no Delve card that is effected by 3shpere. All have a CMC higher than 3. (Logic Knot for 0 not withstanding.)

[cdr]

There is no Delve card that is effected by 3shpere. All have a CMC higher than 3. (Logic Knot for 0 not withstanding.)

I meant that prior to the delve/convoke rules change last year, you were still on the hook for Trinisphere no matter how much you delved since it was a cost-reducer.

Trinisphere checks total cost (the only card to do so), not converted mana cost.