Who is the biggest enemy of Lord Vishnu?

Who is the biggest enemy of Lord Vishnu? Biggest enemy in terms of :- (1) Physical strength - Hiranyakhsa, who was an Asura, had galaxy destroying level powers. Hiranyakhsa took the Bhudevi 🌎 and dropped it under the cosmic ocean 🌊. Hiranyakhsa had the power to rip entire solar structure using his brute strength. Bhagwan Vishnu took the form of Varaha to defeat Hiranyakhsa. (2) Acquiring the status of God - Hiranyakashyap. Hiranyakashyap became a god by creating havoc among the Vishnu worshipers. He defeated the gods and at a point there was no one to challenge his supremacy and thus he was worshipped. (3) Brain - Ravan - Ravan was indeed the most genius and highly knowledgeable being. He was Rāksas, born from Maharishi Vishrava and demon queen Kaekasi. This is was the reason he had high intellect with superhuman strength. Ravan not only acquired celestial weapons but also created some deadliest infallible arrows for defeating Devas. Ravan was master in warfare and used the best ways to counter opponents who were more powerful than him (4) Time taken to defeat - Madhu & Kaitab - The Asura brothers with their boon, became powerful enough to fight against Bhagwan Vishnu for 7000 human years. It is mentioned in the Bhagwat Purana that they had boon, they would be killed by their own consent. (5) Successful in target - Hayagriva - Hayagriva wanted to steal the Vedas from Bramha and acquire everything from it. This was finally done by him which resulted the destruction of the first Manavyuga and start of Maha Pralaya. Hayagriva was defeated by Bhagwan Vishnu in his Matsya avata