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Ninjago: The Crystal of corruption (Dawn of Corruption X Ninjago)

After the end of ninjago and before the start of dragons rising, while sensei wu is making tea, the ninjas arrives with some bad news, the city of ninjago got caught in a strange crystalline like growths that is growing everywhere and it caught jay. horrified, the ninjas and their sensei went to the city to notice a mysterious apostle.
"You've come too late.." The Apostle of apothus said, "this realm will be ours to bear!"

The mysterious apostle is then defeated by a symbiote named echo, who gave sensei wu and the ninja's their info about the god nyx, the black sun and the corruption surrounding it.

Since then, many innocents are saved or lost but the corruption still spreads, jay is saved but due to the power of nyx, he's almost corrupted but the primal element of lightning saved him.
Ninjago became a hot spot for hunting down powerful corruption like beings

Corruption : A Element that is a distortion of purity, corruption symbol is that of nyx eye, corruption can spread or manipulate everywhere, but it's weakness relies on the will of the user.

Four corruptive elements: Or the four primal elements of corruption, these elements has been cursed by nyx power, each symbol changes to the eye of nyx and elements surrounding it. Also the element name is bastardized and weapons spawns from it
Inferno : A corruption to flame (Odachi of inferno)
Storm: A corruption to thunder (Hammer of storm)
Erosion: A corruption to earth (Eroding Dual hammer)
Black-Ice: A corruption to ice (Black lich crossbow)