Far beyond your limit called morality

Hell's Gate.

There was only one person Lilou knew who could unleash such power. It was an ability Tilly used back on the mainland, and out of curiosity, Lilou bugged Tilly to explain to her this ability's real nature. 

According to Tilly, Hell's Gate was akin to blood and darkfield. The difference was that the bloodfield mostly controlled the blood that was within it. If the caster of the bloodfield was stronger than his opponent, they could control their opponent through their blood. 

A darkfield, on the other hand, was a level higher than a bloodfield. It didn't have much difference, but a darkfield was more like a dimension. The caster of a darkfield would have the upper hand as its caster would enhance its caster's ability, strength, agility, and so on. It was a double edge though because if the person who could cast a darkfield met a formidable opponent, the darkfield would only suck the life out of its caster.