Make a Wish. Have it horribly corrupted.

[Captain Jigglypuff]

Granted. You become Dolan and ten seconds later you drop dead....

I wish I had some ice cream!

[Uncle Garnetto]

granted. a screaming eye coming up

i wish i was gonna be a long long time
Till touch down brings me round again to find
I'm not the man they think I am at home

(no points for guessing what song i am currently listening to)

[Brawlimar]

Granted, but you are not a Rocket Man

I wish that pokemon eggs didn't take so long to hatch.

[Uncle Garnetto]

Granted, there are no more Pokemon eggs, and there never will be, but if there were any, they would hatch in 10 steps

I wish I had a pet dalek

[Stmacl]

Granted!! The Doctor comes and arrests you for enslaving an endangered space alien.

[Uncle Garnetto]

I WISH PEOPLE MADE WISHES

[Stmacl]

Granted!!!

I wish I wouldn't forget this-

[Draghost999]

Granted. You couldn't finish typing up your wish, because someone comes up and kills you at the last second. That's why you forgot the period and that's why you have hyphen there. Anyway, you wasted your wish.

I wish I could do whatever I want.

[Uncle Garnetto]

Granted... But whatever you do still has consequences

I wish for a turkey sandwich

[Petzbreeder]

Granted, the turkey is still alive though.

I wish I had a Jirachi (so I can make more wishes!)

[Stmacl]

Granted!! It gives you a bad egg!!

I wish I could shake hands with Satan!!

[Brawlimar]

Granted, Satan pulls you DOWN DOWN DOWN INTO A BURNING RING OF FIRE-

Okay, now that my silliness is over, I wish I had a pet Beheeyem that cannot kill anyone and obeys me completely.

[Stmacl]

Granted!! However when you ask it to pick you up it crushes you!!

I wish that the Vannilite's that I'm breeding will have Hidden Power Fighting!!

[Brawlimar]

Granted, but the only other move it has is Splash!

I wish my shiny Flying type from Heart Gold has shiny children in her near future...

[Draghost999]

Granted. I come, cook, and eat the shiny children. Delicious.

I wish for a portable toilet that I can shrink to pocket size and put in a bag, so when I'm driving I don't need to pee.