"The earlier we expand the dungeon the sooner we can create space for our future monsters as well as rake in the benefits brought by being a five floor dungeon." Not only would the daily DP brought in by the mana vein increase, according to Dark's changes, by expanding the dungeon the core would grow in strength. This in turn would provide the dungeon core i.e. Frost with a greater influence while connected to the core thus allowing him to control high rank monsters even if his individual strength wasn't up to snuff.