If my opponent casts World Breaker and chooses to target my Island with the on-cast trigger, can I cast Deprive in response, targeting World Breaker, and return the Island back to my hand so it doesn't get exiled?
Yes, this work. You get a chance to respond to the trigger and when it goes to resolve it will be countered on resolution because its only target is illegal.
Yes, that works. Since World Breaker has a cast trigger, it will go onto the stack above World Breaker itself. You can then take an action when your opponent passes priority (which they need to do before the trigger resolves) to cast Deprive targeting World Breaker. When you pay the costs for Deprive, you return the land to your hand (no one can respond to you paying that cost). Then, it will be on the stack above the World Breaker trigger.
Assuming nothing else happens, Deprive will resolve to counter World Breaker. Then, the trigger will go to resolve but since its target is now illegal, the trigger will be countered on resolution and nothing will happen.
You will end up countering World Breaker and have an Island in your hand instead of being exiled.
Yes. You return the land as part of the spell's cost, so it goes to your hand right in the middle of casting your Deprive before it even becomes cast. The land is safe in your hand, World Breaker's trigger lost its target and will get countered by the game rules when it tries to resolve. And before that, the World Breaker spell gets countered by your Deprive.
Assuming nothing else happens, Deprive will resolve to counter World Breaker. Then, the trigger will go to resolve but since its target is now illegal, the trigger will be countered on resolution and nothing will happen.
You will end up countering World Breaker and have an Island in your hand instead of being exiled.
I thought so, just wanted to be sure
Former Rules Advisor
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