Aloha,
I'm familiar with the Crushing Block / Spiked Pit combo, but is there any reason why the following wouldn't be legal:
Play the Spiked Pit on a hero. When they climb out of the pit, play the Crushing Block and knock them back into the same pit.
This would do an extra point of damage for falling back into the pit and would rob them of one extra movement point, too.
So, is there any reason why this wouldn't be OK?
Dave