The Metal Skullclaw is a flying enemy spawned during the battle with Aegis.
Aegis will spawn the Metal Skullclaw when wearing the bull mask. The Metal Skullclaw acts similarly to the Bone Buzzard, with more HP and higher magic defense. It doesn't hit very hard, so the player can ignore it if they want to focus on Aegis.
The Metal Skullclaws give very little experience and money, so the player shouldn't worry about farming either from them.