So I cast show and tell, put griselbrand into play, opponent slaps down leovold. I'm a little annoyed and worried but glad to get a chance to test against it.
Twice I activated griselbrand on my opponent's turn to draw ONE card for seven life :)
It still helped me win. The worst part was when I had to use forbidden orchard to make Mana and my opponent got a free card from it!