The Poisoned Blade of Darkness

The Poisoned Blade of Darkness is the Mightem of the God Tsukuyomi, possessing two of his Holy Mights: Poison and Darkness.

Holy Might

A Mightem contains within it the Holy Might of a God, though the Poisoned Blade of Darkness, like the Flame of Bortan, actually contains two. They are enchanted to hold them. A Holy Might is the representative power of a God's domain, with Tsukuyomi in specific also having one that pertains to Ophidians. This is, however, Poison and Darkness.

Might of the Blade

The Poisoned Blade of Darkness's power comes from those two domains. It is rather self-explanatory, yet it will still be elaborated on below.

Poison

The Poisoned Blade of Darkness holds no poison on its blade, meaning it cannot actually be wiped clean of poison. The poison only comes out when someone is stabbed or slashed with the blade. Instantly upon contact with skin, scales, organs, or even clothes, the poison seeps out of the blade to hit its target.

Gar Jee

Gar Jee is a famed holder of the Poisoned Blade of Darkness. He was Head Priest of Tsukuyomi in the 540s-560s and one of the most feared fighters in the world due to his overwhelming strength and tricky, poison tactics. After all, Tsukuyomi teaches his followers to fight dirty at all times.
Gar Jee is a Coral Snake, meaning that he is inherently venomous as well. A bite from him, which he will often do in combat, is enough to kill. So one often needs to worry about two different poisons, his natural poison and his Poisoned Blade of Darkness.

It is not just any poison. The blade adapts to its target, knowing exactly the best poison for a situation, lethal or otherwise. Sometimes it is corrosive, sometimes it is paralyzing, and others it can be simply annoying.

Darkness

The Darkness aspect most notably extends to the blade itself. It absorbs all light, meaning that it seems to just be a black blur of nothingness in the vague shape of a blade. However, there is more than aesthetics.
It can create blinding effects to wrap anyone in darkness so that they can be attacked by the user (though the user could theoretically darken their own vision if they so pleased).
Yet its greatest power is its ability to grant Dark Magic to the one that wields it. As long as they are holding the Poisoned Blade of Darkness, even if they have no Magic or a different affinity, they can use the Dark affinity of Magic like anyone born with it.

Limits

There are two races in Totania that are immune to poison, making the blade only weak to those races. The two races are the Anurans, who have organs that filter out toxins, and a race that took those Organs to make themselves perfect. The Zavese Collective, who have the toxin filtering organs in their bodies, are also immune to all poisons, including this blade.