If I have a geralf's mindcrusher on the battlefield and I have a clone that is a copy of mindcrusher and my opponent plays planar cleansing. When mindcrusher and clone die they will both return to the battlefield with a +1+1 counter, but can my clone return to the battlefield as a mindcrusher again? Because they both die and return and the same time. Or can I choose to return my mind crusher first then my clone?
They do not return at the same time. Both have individual undying abilities, and those only return the creature they belong to. So there are two triggers, both controlled by you, to return one creature each. Since you control both, you control their order on the stack, and thus the order in which the creatures return. So you can bring back the Mindcrusher first, with a +1/+1 counter, mill a player for five (this has to happen before the Clone can return because it's a new trigger, placed on top of the stack, so above the undying trigger from the Clone), then return the Clone copying the Mindcrusher (it comes back with a +1/+1 counter, too, so both creatures will again look alike. but the clone does not copy the counter from the original, it returns with its own).
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