Remember that this data is not even suppose to be released. I imagine that this is a LDoN spell, and that it was copied from one of the first poison dots that a shaman gets. The mana usage was changed, but thats as far as the programmer got perhaps. Then poof, a snapshot is taken and the data goes to Testing... course it doesnt matter, the spell isnt in the game yet.
Just wait and see after it changes. It might not even be poison based.