I was watching this guy play a The Unspeakable deck in modern and was wondering about this interaction. Let's say I have Reach Through Mists, Peer Through Depths and Sift Through Sands in my hand, and I control Goblin Electromancer, and I have 4 blue mana available. I cast Reach Through Mists, and in response, my casts a kill spell on the Electromancer. I'd like to respond with the other two spells while I can still afford them so I can get The Unspeakable, so let's say I cast Peer Through Depths in response, it resolves, and then I cast Sift Through Sands. By the time it resolves, Reach Through Mists is on the stack but it hasn't resolved. Do I get The Unspeakable?
(I assume I could avoid this situation by maintaining priority and casting the three spells in reverse order if I wanted, though.)
Sift Through Sands cares whether "you've cast a spell named Peer Through Depths and a spell named Reach Through Mists this turn", but Sift Through Sands doesn't care whether either spell also resolved. (Review C.R. 601.2, especially C.R. 601.2i.) Thus, for example, a spell named Peer Through Depths you've cast may have been countered, and it will still count for purposes of Sift Through Sands.
(I assume I could avoid this situation by maintaining priority and casting the three spells in reverse order if I wanted, though.)
Sift Through Sands cares whether "you've cast a spell named Peer Through Depths and a spell named Reach Through Mists this turn", but Sift Through Sands doesn't care whether either spell also resolved. (Review C.R. 601.2, especially C.R. 601.2i.) Thus, for example, a spell named Peer Through Depths you've cast may have been countered, and it will still count for purposes of Sift Through Sands.