Forum:5th Crystal Beast Issue

Here is the situation:

I have "Rainbow City - Ancient Ruins" in play, and 4 random Crystal Beasts in my Spell/Trap card zones, and one Crystal Beast on my monster zone, this one beign the only monster on the entire field.

Next, I activate Hammer Shot. My Crystal Beast is destroyed.

Question is: Does it go to the Spell/Trap Card zone? Or since it's occupied by Hammer Shot it can't? I'm not sure when does the Spell go to the graveyard...

The same could happen with a same given situation, but when I summon the Crystal Beast (even if the opponent has monsters or not) and I chain a set Torrential Tribute.