Sky style is to mass Sorceresses + Riremen.It is a general warcraft 3 strategy which can do more damage to UD. This strategy is super at the middle stage of the game,so once you tech to tier 3,it is easy to counter with. At early stage,HUM will be creeping crazily till they are forming an army at tier 2.So UD send DK to follow HUM to steal experience,and Ghouls creep creeps themselves,update main base,build two Slaughterhouses once to tier 2 then get to tier 3,Do not create the 2nd hero. Two Slaughterhouses mass Statues only.Get Lich when half of tech 2 to 3,and train the 3rd hero when get to tier 3.If you have money,buy a Orb of Corruption and research Frenzy ability of Ghoul.When those are ready,it is time to attack when UD have 6 destroyers. This time ,3 hero all not have high level,so let Ghouls as tank,use dispel ability of destroyer to stop slow Sorceress have casted. Ghouls counter with Rireman and Footman,destroyers fight against sorceresses. Attention about this strategy. 1.Use dispel immediately or Ghouls not be able to do any damage,and hero maybe kill easily. 2.Hero's ability cast ASAP,and watch out them HP. 3.Tech to tier 3 ASAP for HUM have the advantage at the mid-game. 4.If HUM have 3 heroes,Ghouls round-killed low level hero.