Caligula

Caligula (Roman Emperor) once held a large meeting solely for the purpose to tell the attendants, that if he wanted he can have them all killed. He then dismissed the meeting. He also once waged war against Poseidon. He led 10,000 soldiers to the sea and ordered them to stab it with spears. Another time he marched his entire army towards the English Channel in an effort to invade Britain. Upon arrival to the channel, he decided that he no longer wished to invade Britain so he ordered his men to collect seashells before heading home.