Fate Stay Night

Saber didn't win the fight. I can't help but think that Assassin, realizing that his end was near, held the battle just as some kinda test for Saber. Test for what? Whether Saber deserves to be the one who killed him. Why? As we all know, Assassin is fictional. He's nameless, and he died without honor. But the samurai soul in him wants nothing other than a great battle, where he can give his all and use his secret attack to the fullest. Especially considering that Tsubame Gaeshi was a product of nothing more than pure skill, training and determination. So I see Assassin as a person who only wanted to test the result of all his training against someone who he considered worthy, which was not granted in his life. That's why he's so glad when he met Saber, because to him Saber is the one. He wanted to put his all in the battle against Saber. Unfortunately, even before the final battle, he's already at his limit. He got no time left. But he was determined to die an honorable death this time, and so he used the battle to test Saber whether Saber can be the one to grant him that honor.

Lol, yeah, Assassin/Tsubame Gaeshi is my favorite in F/SN.

On the final battle, Assasin was already near-death, there was no purpose for him to stay guard there as Caster already died, but he wanted to fight saber, the desire kept him to stay there.
In the fight Assasin's determination to fight even made him injure his sword by using it to block Saber's attack. By the way I see it, that caused Saber to dodge the imperfect Tsubame Gaeshi later on, which is I think that as a method to furthur end the battle quickly.

In my opinion, Assasin already knew he would lose, but would not want to die and diseapear meaninglessly around the corner, therefore wants to end all of this with a fight with saber, because that is only the time he truly felt himself. I believe he did not consider winning or losing, he just wanted to end this, and gave his all for the result.

Conclusion, what he seek is not honor nor victory, what he seek is a meaningfull ending to his life in this world since his going to fade away sooner or later.

Btw, I don't think he made a mistake in that fight. Most likely he knew that monohoshizao is going to break straight away if he clashed it with excalibur. I think he just faked his surprise as to not injure saber's pride and also to create an opening on the actually-invincible-my-awesome tsubame gaeshi. if not so, I can't find any other way to explain him saying there would be no better end than to die under saber's sword.

Assasin already knew he is going to lose either in a long fight or a short fight. Therefore he made it short, by purposely
- Blocked his sword with saber ( result in a bend and explained later on )
- Moved to level ground ( Forcing them both to be able to use their upmost skill to end it quickly )
- Creating an opening for saber on Tsubame Gaeshi, the bend on the sword makes saber thinks that that is the reason for the flawed Tsubame Gaeshi.

yeah, he could let Saber through. He let Gil through because he had no business with Gil at all. But he had no other wish except to fight Saber, of course he wouldn't let her through. Holy Grail or whatever, he didn't give a damn.

Btw, I don't agree with him being able to change the angle of the technique just to create a flaw in Tsubame Gaeshi. First of all, that technique is a multi-dimensional refraction phenomenon, which lets him cover all angles in his attack range. So simply changing the angle won't do. The slashes will be tilted, but the fact that it covers all angles in range won't change. So I think even if he changes the angle, Saber's head would still be chopped off anyway. The only way for him to create a flaw in Tsubame Gaeshi with his sword in good shape is to change the direction, but that would be very insulting to Saber, and also foolish of him. Why would someone as good as him mistake the direction of an attack?

Also, the other reason that made me think Assassin bent his sword deliberately is that it kills two birds with a single stone. It's hard to create a flaw in Tsubame Gaeshi with his sword straight, and by clashing the sword head-on with Saber, he managed to make both of them stand on the same level. Remember that Saber is fighting in fear because she experienced the imperfect Tsubame Gaeshi once, and knows very well that the perfect one is a sure-kill. So she's being too cautious with the battle to avoid letting Assassin to even have the chance of executing the move. She assumed that Assassin will only parry her attacks and Assassin, who's short in time noticed that and clashed their swords to catch Saber off-guard and seized the chance to stand on the same level, all at the cost of bending his sword in the process. So that's why I think the last Tsubame Gaeshi is just a test of some sort, all because he's racing against the clock and didn't want to disappear mid-fight.

Bah, Saber beat him fair and square. While I don't think that Assassin was a 'bad guy,' he was a neutral-selfish character. I don't think he cared about anything beyond testing his swordsmanship, and Saber was /the/ person to test against. He wanted to test the utmost of his skills, and would not have thrown the match in any way.

Saber wouldn't have been able to exploit the weakness in his attack without having superior skill. She won by being the better swordsman.

Lol, Saber herself admitted that Assassin is the superior swordsman in terms of skill. And if she was truly superior she would be able defeat Tsubame Gaeshi head on anyway, no need for Assassin to go outta his way to bend his own sword just because Saber was stalling the fight, due to her fear of Tsubame Gaeshi. I wonder whether you actually read the VN, or just watch the anime.