### Clue: Depart agitatedly; it may explode! (6)
### Answer: PETARD 
 ### Explanation: Definition: it may explode
  **Anagram of**(agitatedly) DEPART.  Another nice surface – if you don't run off fast enough, you will definitely be "hoist by your own petard".
Answer: A firecracker, or, in a bigger version, a bomb designed to blow a hole in a door or wall.  Interesting etymology, from Latin meaning a fart – a mighty big one, you could say, in the derivative usage!