The Slithersong is a Mystery class dragon that was released on January 29, 2016. It can be bought for 750 gems (600 gems for members).
Very similar to the Death Song, the Slithersong is faster and has a higher pitch and turning rate while possessing slightly lower health. Despite having the same shot limit and base damage as the Death Song, the Slithersong has a lower firepower rating.
The two species share similar markings and color options but have their own unique animations to help set them apart from each other.
Despite gaining energy from eating eels, the Slithersong is ineligible for the Stable Mission 'Eels!', which can be done by other eel-eating dragons.
The Slithersong was firstly released in the game "Rise of Berk", where it is considered as the main species, with the Death Song being a variation. In School of Dragons, while it's acknowledged they are related (On the release note it's stated that the Death Song is "its kin"), no more details were given about their relationship.
Notes on release Edit
Prior to the official announcement, a listing for the Slithersong egg was discovered in the Trading Post by multiple players on the 28th. The egg appeared and then disappeared from the store at least twice in the intervening hours. Upon first being found by players, the Slithersong egg was listed with a full price of 600 gems (non-members) and on sale for 396 gems. Both known times that the egg appeared in the store, it displayed with a placeholder image of Hiccup and Toothless wearing Snoggletog hats. Once the egg was officially released, the placeholder image was replaced with the proper graphic and the full price was raised to 750 gems (non-members). Immediately following its release, the Slithersong egg remained on sale for 33% off (495 gems for non-members) for an unknown number of days.
At least one player who purchased a Slithersong egg during its pre-release appearance reported having problems hatching the egg.