Fraudrin is a part of the current Ten Commandments as the Selflessness, he thinks himself a stand-in for the lacking primary member.

Power Level:

In Seven Deadly Sins, power levels are described as a complete number, the whole being blended into 3 categories: magic, spirit, and strength. The total power level is not a criterion of who clearly wins a fight, it’s simply a lead to who’s major expected to win. For instance, someone with a comparatively low power level yet super magic can strike down someone with a great power level if they don’t have a great plan to combat. The spirit level is a type of control in battle, willpower, etc. Magic & strength are self-illustrative.

Full Power Of Fraudrin the Selflessness

• Age: 554
• Weight: 1521 lbs
  
• Height: 13’9″

Behaving like a human is a beloved hobby, & he has begun to fancy Dreyfus’ body.

Power Level: 31000

• Magic – 13000
• Spirit – 3000
  
• Strength – 15000

Commandment- Selflessness

He was not truly given the Commandment by the Demon King, he simply took the name when he displaced Gowther.

Strength

While stepping off from Denzel & Deathpierce, he stated that he could have comfortably defeated former selflessness holder, even with his magic bound & then he offers a terrifying power to make this case clear.
Meliodas stated that Fraudrin isn’t truly worthy of the title of one of the current Ten Commandments, something confirmed when he was the simplest one to beat.

Speed

Responds to Hendrickson’s strike from behind.

Durability

Fraudrin holds immense durability, as he appeared completely unharmed after being caught by Tarmiel & Sariel’s Omega Ark.

Magic

• Full Size
  Fraudrin gets much larger, reducing any loss he may have suffered before changing. His strength and durability increase proportionally.
• Heart Manipulation Spell
  Fraudrin can control the body of another person, commanding them & gaining their thoughts and skills. He holds some level of restraint even after leaving. Those with abnormally great spirit can withstand him.
• Self-Destruction
  Fraudrin can collect his life energy & deliver it in a cataclysmic blast.

Source: Nanatsu no Taizai Wiki

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