In a couple of weeks cards with the madness mechanic, Eldrazi Processors, and Eldrazi Displacer are going to be in standard together. The text for Madness reads as follows:
“If a player would discard this card, that player discards it, but may exile it instead of putting it into his or her graveyard” and “When this card is exiled this way, its owner may cast it by paying [cost] rather than paying its mana cost. If that player doesn’t, he or she puts this card into his or her graveyard.”
With a board of Eldrazi Displacer and some ETB Processor like Wasteland Strangler, can I respond to a card being exiled through madness by displacing my Wasteland Strangler and putting the exiled card into the graveyard, thus effectively countering madness and triggering my process ability?
If this is the case what is to stop my opponent casting the exiled card in response to this?