Screamers of Tzeentch

Being corporeal manifestations of Chaos, Daemons' attacks are magical and can wound ethereal creatures. etc. This includes any special or ranged attacks they may have.

A flying unit are skirmishers

In any Chaos turn where the Chaos player hasn't declared a charge with them, Screamers can attack an enemy unit which is not inside a wood or a building by moving over it during the Remaining Moves pan of their Movement phase. This inflicts an automatic Strength 3 hit per Screamer and the enemy cannot fight back — these hits count as missile hits and may force a Panic test. A Screamers unit may only use this special attack against one enemy unit per turn, even if they fly over more than one unit in that Movement phase.