THE DESTROYER, otherwise known... as eric.

[u/EntertainerPure8440]

Lord Voldemort - Tom

Mister Incredible - Bob

The Son Of God - Yeshua

Basically, really intimidating nicknames used instead of birthnames, the likes of which aren't intimidating at all.

Title taken from this video (timestamped).

• LORD VOLDEMORT (Harry Potter): otherwise known as Tom.
• MISTER INCREDIBLE (The Incredibles): otherwise known as Bob. My man was genuinely named Robert Regular lmao
• THE SON OF GOD (New Testament): otherwise known as Yeshua, an extremely common name back then.

[u/Dogdaysareover365]

The demon in the exorcist has many intimidating nicknames, but its named pazuzu