The bees were flying brawlers who relied on their sharp stinger and powerful mouthparts to defeat their enemies. Unfortunately for them, they couldn't reach her before she fried them with lightning.
Arthur observed her power while he fought his own battles. What he noticed was that she couldn't control her power accurately.
He wasn't surprised by this because she lacked a divine sense for fine-tuning and control of mana. Her situation reminded him of Thor and his rank 3 golem.
She can't control her power, just like Thor couldn't properly control the powerful golems. She also couldn't sustain her power output for a long period of time, just like Thor.
The reason for why she couldn't sustain the power she gained from the world is the same as why Thor couldn't sustain controlling the power of the golem. The reason was that controlling the power of the world placed a heavy burden on her mind.
