The necromancer turns into a flurry of Voidic magpies that explode outwards from the pont of casting to a space up to 60" away in an unoccupied space ze can see, forming a 10 foot wide line behind zim.   Creatures designated by the necromancer in the line from where the necromancer cast the spell to where ze ended up must succeed on a Constitution saving throw or take 3d10 + proficiency bonus in necrotic damage and have their speed reduced by half until the end of their next turn.   On a succesful savings throw damage is reduced to half and speed loss is reduced to a quarter (rounded down to a minim 5").