There's no such thing as perfection.
Even the mightiest dragon had a gap between its scales, and the Primordial One fell from the creations' negative energy. Naturally, a mortal made Lord Castle would have several blind sides.
In the first place, the Realm of Greed wasn't the best in fighting power. Their soldiers weren't as strong as Wrath or as good as Gluttony--which was full of soldiers with centuries of experience. Ironically, the Castle Guards getting focused on the Lord Consort as well as the lakeside forest created some holes in the Castle's overall security.
The moment the Lord of Greed was sighted in the Realm of Wrath's warcamp, a scroll burnt in the darkness of a forgotten room beneath the Temple. Several cloaked figures straightened their back and slipped inside a tunnel that hadn't been used for centuries; the existence obscured in history.
It was the tunnel that would bring them inside the Castle ground.
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