In response to you playing the Sol Ring, I wish to cast Fling on my Rector, targeting you. Response? In addition, sac-ing the Rector triggers it's ability. If you counter the Fling, you don't take damage. But the Rector was sacrificed as a cost, so it's ability cannot be countered unless you have Stifle or Voidslime.
Response?
Ransac
Life: 20
Hand: 4
Library: 50
In Play:
(U) Tropical Island (U/G)
(U) Tundra (U/W)
(U) Island
(U) Birds of Paradise (0/1, Flying, T: Add 1 of any color mana to your mana pool.)
Land Tax
On stack: Fling, targeting mooseman (2 damage)
Graveyard: Academy Rector
RFG:
mooseman
Life: 18/16
Hand: 6
Library: 49
In Play:
(UU) Mountain 2x
(U) Island
(T) Fellwar Stone 2 T: Add to your mana pool one mana of any color that a land an opponent controls could produce.
(U) Sol Ring 1 T: Add 2 Mana to your mana pool. (Not in play, yet)
Graveyard:
RFG:
Ransac, cpa trash man