Question on Prosperity

[KDenz81]

Player A attempts to cast Prosperity.  He pays the initial casting cost of and puts Prosperity on the stack.  

Player A then asks Player B if they have any responses.  

Player B doesn't have enough untapped for a counter and no force in hand.  

Player A then chooses to tap his Mana Crypt, Sol Ring, and pay 4 for .  And forces each player to draw 4 cards.

Can Player A do this?  The same thing would apply if it were Fireball, Blaze, or any other X spell.

[Rico Suave]

Player A attempts to cast Prosperity.  He pays the initial casting cost of {U} and puts Prosperity on the stack.  

Player A then asks Player B if they have any responses.  

According to the rules in this situation, Player B can pass priority and Prosperity will resolve for 0.  All costs must be paid up front for a spell in full before passing priority to the opponent.  Once the opponent passes, that Prosperity then resolves for however much mana was invested in it before passing priority.

For another example, many players used to try and cast Balance, see if their opponent was going to counter, and if not then sac all their land to Zuran Orb for lots of life and an Armageddon.  That is an illegal play, and if your opponent decides not to counter then by the time Zuran Orb can be played again the Balance is in the graveyard.

[Jacob Orlove]

For another example, many players used to try and cast Balance, see if their opponent was going to counter, and if not then sac all their land to Zuran Orb for lots of life and an Armageddon.  That is an illegal play, and if your opponent decides not to counter then by the time Zuran Orb can be played again the Balance is in the graveyard.

Technically, back when there were interrupts, that play worked, but I won't get into the details. It's certainly not legal now, and hasn't been for years.

[rvs]

I would like to point out that it is the responsibility of both players to make sure there is no doubt about the gamestate. So if you are unsure, ask. If these situations would occur at a general T1 tournament, the most likely solutation any judge will have is to back up to where the spell is initially on the stack.