Killing a king is no small matter.
Even a destitute Dwarf King, even if the Dwarf Palace had just been built, already housed a massive Defense Magic Array, heavily guarded by troops and protected by legendary warriors.
The Dwarf King was also a Vampire, a creature vastly difficult to eliminate without direct sunlight, capable of reattaching its own severed head.
Thus, when Seth Yuri heard Amberser declare his intention to kill the Dwarf King, his initial reaction was disbelief.
Yet, considering the special nature of the Magic Mirror, could this heroic predecessor kill through the mirror? If that was the case, as long as there was a Magic Mirror inside the palace, there might be a chance, a Sunbeam or a Daylight Spell could easily slay an unprepared Vampire.
But would he truly follow through with it?
Just because he owed his uncle a drink, he would help him assassinate the Dwarf King?
