Darcel

The Darcel series is a series of DARK Machine-Type monsters, and another sub-Archetype of the Machine Emperors (or Meklords, which it has a form of). These parts are all purple in color, and when combined, they have a vaguely bat-shaped form. What makes Darcel unique is that unlike all other Machine Emperors/Meklords, Darcel's Guard Parts actually get weaker in terms of DEF as they level up. This is because Darcel utilizes an Anti-Piercing strategy with Darcel Guard 5 negating Piercing Damage and Darcel Guard 7 sending the damage right back to the opponent. The fact that Darcel Guards 3, 5, and 7 cannot be destroyed in battle makes Darcel formidable, but the parts are still vulnerable to card effects. Also, the strongest Attack and Guards Parts for Darcel require a certain Trap Card to Summon.