Chromatic Star timing question

[Lord Seth]

Suppose I have an Aether Vial on 2 with a Meddling Mage in hand. My opponent cracks a Chromatic Star for Red, intending to cast, say, Pyroclasm. Now, when it goes to the graveyard, its trigger ability goes on the stack.

My understanding is that sorceries cannot be normally played while anything else is on the stack. Therefore, they can't cast the Pyroclasm until after the "draw a card" ability has resolved. Does this mean that I can use my Aether Vial, while that trigger is on the stack, to put my Meddling Mage into play and name Pyroclasm (or whatever other non-Instant spell I expect they would use the mana to cast) to stop them from casting it?

[Julian23]

You can only use your Vial to foil his plan if your opponent misplays. If he activates the Chromatic Star for red mana and then puts the triggered ability of it on the stack, you will get priority to activate your Vial.

However, if he first announces Pyroclasm and then pays with Chromatic Star's mana ability, the trigger only goes on the stack after Pyroclasm has been cast.

In a way, it's the reverse kind of "trick" as in casting a lethal Lightning Bolt on your opponent with City of Brass while on 1 life.

[cdr]

Also, if the opponent is doing out of order sequencing (sloppy but legal play) like "sac Star for red, play Pyroclasm" all at once without putting the trigger on the stack or waiting for a response, they're allowed to correct the sequence if you ask them to do things one at a time. Someone playing sloppy might still mess up the order if you ask them to clarify though.

[iamajellydonut]

Note: If it was Chromatic Sphere (http://magiccards.info/in/en/299.html), it would be considered a mana ability and you would not get a chance to respond.

[cdr]

Note: If it was Chromatic Sphere (http://magiccards.info/in/en/299.html), it would be considered a mana ability and you would not get a chance to respond.

Chromatic Star does have a mana ability, the draw is just moved to a trigger where with Chromatic Sphere's draw is part of the mana ability. (Which has caused some rules problems over the years; they eventually decided that if you activated it while casting a spell or activating an ability, you couldn't look at the drawn card until the cast/activation was complete).

[Meekrab]

Chromatic Star does have a mana ability, the draw is just moved to a trigger where with Chromatic Sphere's draw is part of the mana ability. (Which has caused some rules problems over the years; they eventually decided that if you activated it while casting a spell or activating an ability, you couldn't look at the drawn card until the cast/activation was complete).
Yep. On MTGO for example, the card shows up in your hand but you can't see it unless you manage to discard it while your original spell is on the stack.