I think these pieces are problems too though much less obvious, in that people "pre-counter" this by using minions with all 3 front attacks. Lilith has this effect as well. These in particular horribly punish having any holes in your army. If a SoulKeeper gets on your row 3 uncontested and one of the Ghost attacks it can make can target the king, it can infinitely ghostify your row 2 unit over and over until checkmate is basically forced.

-main_gi