Beating Arcade on highest difficulty (Edit: I did it)

[Samvega]

How I did it: Mirror-match as Samuel and long guard + Y. The range on the move is great, and you can snipe the enemy after they put themselves out of balance with a whiffed move.

ORIGINAL POST:
I've beaten the boss with all characters before, but not on hard. On hard, the boss doesn't flinch, so one attack causing a flinch into a combo isn't enough to win a round, and I am struggling to get two wins in a row. Any tips? I don't know if the fight has changed much over time, it might be that patches have changed the boss AI behaviour, and old tips won't work as well.

The camera being different also sucks, because it makes the fight harder. And not seeing damage and stamina also sucks, because it makes the fighter harder. These are perfectly acceptable choices for a boss fight, as long as the boss fight compensates in other ways to be possible.

[Samvega]

The fandom wiki has no tips on Evil Samuel (the boss), sadly.

[Samvega]

Accidental double post.

[Subutai]

The key is to time your attacks really well and aim for lethal shots to the head and the arms. While the armor protects him well, you can still kill him quickly if you aim lethal injuries at those targets. You just cannot trade with him.

[Samvega]

Did it! Mirror-match as Samuel and long guard + Y. The range on the move is great, and you can snipe the enemy after they put themselves out of balance with a whiffed move.