[@Beloss]
You're of course welcome to contest rulings or offer your own argument. With that said, I will be blunt in saying that the odds of a ruling being changed after the fact, while nonzero, are low. As such, when you've said your piece, I ask that you don't harp on about this to a heavy degree. 

Now then.

[quote]
Shouldn't you have waited for the other characters to have posted before issuing your response? Rostam was being supported by 3 Archers during his charge, all of whom are going to get shots off before his Charge is complete. The idea of advancing under ranged support is that the target has to fend off ranged attacks while the melee unit approaches, hence protecting him from being singled out. Maybe all three archers do decide to betray him and not shoot, but we really don't know that yet. You broke posting order to launch a killing blow, while ignoring everything everyone else might be doing in the remaining time.[/quote]

While I have been lenient on this front, the fact remains that:

[quote]There is a 24 hour period you must try to reply to a post within. I will be lenient with this, but if you're in a fight, someone swung a sword at you, and you didn't post within 24 hours of that sword swing, then there's a good chance that your character will stop having a head. The same applies if you're talking to a character; if it's been 24 hours since your last post without a reply, you're free to walk away. Of course, if you have real life troubles or will have difficulty meeting that threshold, let me know so I can grant leeway.[/quote]

I waited for three days and eight hours after a post before posting with NAGATO's attack. I was not told that anybody had real life issues or received any request for an extension. I was not told by any player that they had plans on posting something relevant to the fight. If I had, then I would have waited, but after having waited over triple the length that I had said to, there was no reason to continue delaying.

Most damning of all, though, is that I explicitly gave [url=https://www.roleplayerguild.com/posts/4358697]a full day's warning that the fight was about to move forwards[/url]. 

If anyone was going to offer support to Rostam, they should have spoken up during those three days, or especially during that last one day time frame.

[quote]On speed related matters, I'm not thinking in terms of breaking or not breaking the sound barrier or anything like that, nor did I think I was expected to. Most, in fact, all Role Plays I have been a part of don't do this, simply because of how complicated it makes everything, especially with humans running around at 10 and 20 miles per hours at the same time. 

If you are going to apply these standards, you should have told me first, and assigned an exact speed for Rostam and his Mount during the character creation.

The points you make about Servants being able to turn faster than their mounts can is moot since I assumed that either way it would be fast enough. I even factored this rule in by having Rakhsh take a sprain from turning faster than horse's are meant to on this occasion.[/quote]

I apologize, but this was also dealt with in the rules. 

[quote][b]Keep in mind that we're following canon rules and mechanics here, first and foremost.[/b][/quote]

I've already explained why, under canon logic, it is reasonable to know that Rakhsh would be inferior to Rostam in burst movement speed. Moreover, as was stated above, the onus is on you if you are unaware of the nature of what you are applying. If you are not clear on the abilities of your character, then it is important that you ask this in advance; if you do not, I will assume you have done the reading and are aware of what having a Phantasmal Beast mount means.

[quote]For trying to tank out the attack, you just finished shooting Rostam with an arrow, and telling me I was foolish to try and tank it. Noble Phantasms use difrent standards of power to ordinary attacks, and there is no case I can think of of a Servant surviving a direct hit from an A rank one, except for Hercules. 
Besides, if Rostam can tank this attack, then shouldn't he still be alive anyway? Trying to dodge it doesn't lower his passive defenses, and since it's a wide range blast, holding his mace out or something isn't going to do anything.[/quote]

You're misunderstanding. I'm not saying Rostam should have tried to tank it with his body, I'm saying that a viable method would have been using Rakhsh's Prana Burst to clash against the attack. If Rostam just sat there and tanked it, he would have died as well.

You are in possession of a B+ Noble Phantasm, and the light was equivalent to an A rank, after all. While mystery and power don't scale 1:1, the fact that 80 is greater than 50 should have been something of an indication.

[quote]Dismounting from the horse and then jumping away would have taken longer in this case, since it takes a moment to free yourself of the saddle and then change directon. I knight cant just spring out of the saddle whenever he wants.  
When Alexander escapes Excalibur, he is jumping from a moving platform which he is already standing upright on.[/quote]

This applies to conventional humans. Servants are freaks who can accelerate to mach 4 in a fraction of a second.

[quote]Not attacking at all I guess is an option, but I already exercised that option when I had him take his Master away to safety first. 
When Rostam charged he was not charging head on, was ready to prepare evasive maneuvers, and he was being supported by 3 archer Servants, who you didn't let post. This hardly counts as reckless, in fact, I cant honestly think of any better opportunity for a mounted melee character to try an come to grips with a ranged one. 

I really don't see any circumstance which Rostam could have survived this, aside from not attacking at all, which I had already done. Continuing to delay longer would have been bad characterization, as well as being tactically bad. 
[/quote]

I will be blunt: You had Rostam charge directly at an enemy who had just entered a more combat-capable form at the same time that he was channeling enough prana to fill the Eastern Field in one of his hands. If you sincerely believed that you should have had this supporting fire, then you should have brought it up before my previous two posts, but as already stated, I myself had no reason to believe such fire was coming in a reasonable time. 

The presence of evasive maneuvers given the circumstances is relatively meaningless given what has already been said about Rakhsh's speed. This is doubly the case given that it has been displayed in previous events such as the kidnapping of Stirner Cartisius that NAGATO's physical parameters are well above those of a standard Servant, as it should be for something capable of matching the "nuke" of a Servant with sheer power. 

As an aside, I'm not really sure why you are viewing NAGATO as a ranged combatant, considering that IC he committed zero ranged actions before the release of the Jewel Sword, and OOC his matrix calls him a "ridiculous close-ranged combatant".

I'm sorry you're unhappy about this. To be quite frank, I didn't expect Rostam to die in this situation, but nonetheless, that is what has happened here. The Archers' support is vacuous, given the rules and especially given the warning post I provided. The defensibility of Rostam's own actions is moot given the prior knowledge about the enemy and the knowledge about Rakhsh that was presumed on account of being very prevalent in character materials.

If you have further objections, you are free to voice them, but I'll be clear in saying that while I can understand your annoyance, I genuinely don't think you have a leg to stand on from the perspective of the logic of the IC.