Thanks, Amy. As you can guess, the toolbox figures significantly in the climax of this episode.
I thought it was dumb when 1) Jonathan revealed the green crystal 2) Clark immediately crumpled in pain 3) Jonathan stood there for a few minutes before putting the pieces together. Here, both he and Clark react a bit more quickly.
In the episode, Clark and Lois weren't this far along in their relationship at this point. And Cat is dealing with her own emotional loss - which we'll see more clearly in the next chapter. Which will be up in - oh, a few.