It's a waste to kill Azaela, Grain can kidnap her easily and torture her for the pain they cause to him. He can turn Azaela into his personal slave as ease.
The prince must never hear the tale a legendary blacksmith who from a son of blacksmith to a noble knight who beat the crap out of Hungarian-Cuman invaders, and when the hero come to everywhere, the people just keep praising "Henry come to see us!!".
A laboratory building without backup power sources, lightning proof, no security at the experiment floors to prevent unauthorized people wandering around, awesome.