Before I don't understand why socket-type bolt extractor, while left-handed drills are more than good at the job.

 

Turns out not in tight corners!  And c**** some sly Toyota designers put 5mm allen to the oil sump, and said torque-it to 23ft-lbs-ish, inside the most inaccesible spot ever! 

 

There's no word could express the joyness seen that bolt starts rotating, after fighting with it a whole day.  xD

 

 

 

Or you could have hammered a spline drive into it, sometimes works. That kit you have there is what is often used for removing locking wheel nuts.