She moves while always floating in mid-air. Like Arme, she lacks the ability to dash and run, but she has other ways of compensating for this. She can chain combos while in the air and can also summon her minions to help her during battle.
Harbinger can summon Bastion Mary who, unlike Garouille, can be controlled and the player can time her attacks. The improved AI allows for more successful fights. The all new jump and dash attacks serve to ameliorate the frustrations of running dungeons as a Summoner. http://grandchase.gamerage.com/guides/Characters_ley.aspx