Dota2’s Wraith King came from Skeleton King(In game character name was also Leoric BTW) from Dota 1 which was in turn copied from King Leoric from the original Diablo. So basically, Dota ripped off Diablo not the other way around.

My friend, it is clear you have not seen this movie and are basing all your assumptions on the hyperbole of disappointed fans. So let's see if I can help you out a bit.