Forum:Horn of Heaven, Bottomless Trap Hole

I've always wondered about this but no one I play with has been able to answer:

Why can you NOT use horn of heaven/black horn of heaven to negate the special summon of a card summoned by a card effect (monster reborn etc), but you CAN activate bottomless trap hole in the same situation?

Would really appreciate someone explaining this. Thanks! 74.233.38.124 14:50, 14 August 2009 (UTC)