There were constant waves of Amonros rushing towards the enemies as they started launching tides after tides of kamikaze attacks at them. Grimm did not bother to lift a finger to deal with them at all as the Greedy Flame Giant had already beaten all of these suicidal Amonros into lifeless meat bags by simply swinging his massive powerful arms around.
The situation was pretty much the same with Millie too. These low ranked creatures could not get close at all because they were all slain by Millie's ice statues and Snow Panther on the ground. The Ice Phoenix did not even need to descend to deal with these nuisances.
Not bothered by the oncoming attacks, Grimm made use of the opportunity that his giant had created to quietly study the different laws of nature of the Shadow World.