So did the object being thrown in vaporize, was it deflected by the bolt, or did it make it all the way to the pillar?

Corwin (Switching colors since Kanti is using the seagreen)

First, Knowledge Arcana or Spellcraft to figure out the magic behind the pillar.

(1d20)[3] Add 10 for a Know(Arcana), or 6 for a Spellcraft

SEcondly: Well we've already seen one switch, back on the dragon's head. Is it possible that if someone who can make it by the spikes flips it, it'll turn off this trap?