One person comments a wish.
The next person grants it but corrupts that wish then makes a new wish.
e.g.
"I want a collection of mint sealed G1 Transformers."
Granted, but they're all Wheelie.
Oh, and your wish must be stated in a single simple sentence; only ONE condition per wish. Do not attempt to "corrupt-proof" your wish by making complex run-on sentences with various conditions!
Okay, my wish -- I wish for Time Warrior.