How do you defeat psycho mantis while playing on epsx?

To defeat Psycho Mantis in Metal Gear Solid while using EPSXe, you need to use the second controller port. First, plug your controller into port 2, as he reads your inputs from port 1. When the fight begins, he will try to predict your movements, but with your controller in port 2, you can attack him without his interference. Use weapons like grenades or the SOCOM pistol to deal damage until you defeat him.