Meanings of cruel prank in English

If Gavin had believed in Orholam, he'd have thought it a cruel prank.

If somebody was playing a cruel prank against Miss Lovejoy, then I had no idea who.

But alas, the fates which dogged Peter in his love-making had prepared an especially cruel prank that morning.

Emmeline winces in pain at Bodley and Ashwell's cruel prank and, to her own astonishment, hot tears spring to her eyes, falling onto the pamphlet.

I've heard of some cruel pranks, but this one beats them all!