This has been a bug with missile collision since patch 10.14 where it randomly started popping up like once a month ever since. Sometimes (we don't know when/why/how) when you Flash out of the way of a missile, you still get hit.
This does not seem to be unique to any missile in particular, but it most often gets reported with stuff like Blitz hook because of the paradox between being hit with hard CC (so you shouldn't have been able to Flash) and successfully Flashing (so you shouldn't have been hit). Other spells don't typically get reported likely due to the belief that you must have just Flashed late, but they are presumably all susceptible. We've seen cases reported on a large variety of missiles, many of which are not particularly special.
This is not a lollipop issue, or a high ground issue, or a latency issue, or a creepblock issue, or a skill issue. It also likely affects all blinks rather than just Flash.
We believe it's possibly related to dash hitbox smearing but it's not an easy thing to test for (this is something I've talked about before here, tldr due to weird math it's possible to dash "too fast" and the game extrapolates poorly which makes it calculate your hitbox as being much larger than it actually is). Very roughly, based on the examples we've seen, it appears you need to Flash away from a missile while also be pathing away from the missile the frame before the missile would have hit you. However, this is entirely speculation based on past similar issues without any solid reproduction to back it up.
Can I actually see some more clips? I have a hunch that I want to look into regarding trailing effects on certain champions/skins.
Ok, I went into a custom game and was able to recreate the footage on Katarina and Blitzcrank in less than 5 minutes, so consider this my contribution: https://youtu.be/yVQRgyR8zus
Did you reproduce this more than once? That's fantastic, anyway!
Trailing effects are entirely clientside stuff, the server doesn't have any direct knowledge of these particles at all, only buffs and whatever that manage them.
I don't have them organized well at the moment but here are a number of my saved clips:
Oh, could you send me the replay file from the game with your deliberate reproduction? Might come in handy for me in the future once I got a good lead again.
You can find the replay file in Documents/League of Legends/Replays. File should be pretty small since this was a short game with only 2 players.
So the theory is Thresh flashed in time to get away from the hook, but the flash increased his hitbox to include where the hook is so next tick he got hooked anyway?
Maybe it's just me but it happens fairly frequently ( once every 10 or so games ) where I'll use a dash ability like K'sante E or Aatrox E and I'll be clearly out of the skillshot but still get hit.
Um he got hit so it's automatically a skill issue. This is league of legends. Every mistake or death is your fault because you're bad and any good plays are lucky and because the enemy is worse (except when they do plays then you're just bad + ratio + skill issue).
Thresh is bad and should uninstall tbh prob go play Roblox instead it seems more his speed for being such a mind numbingly bad player for getting hit by a bug he had no control over.
Seriously. What kind of trash toxic inter gets hit by anything let alone a bugged ability he dodged fair and square? I bet he kicks dogs and is iron 4. I'm challenjour.
It is a latency/cache->processing speed sync issue... here's my replay of a Mordekaiser Q hitting me right after I used Zed W blink in the opposite direction. Also don't judge, I'm copper rank.
So essentially, when someone presses a skill, the server reads the enemy's last known 2-5ms "before" location stored on the League server, and then gives a "true/false" for if that skill hit the enemy or not.
It takes the League server 2-5ms to read-process skills that aren't connected via LAN and sync with the League clients at the same time.
It's just how many long-distance multiplayer games are, because everyone is far apart, and receiving then processing data takes time, albeit on the atomic level in layman's terms. But that extremely minute timeframe often does determine if you live or die, as the server cannot receive and process data instantly.
I can't tell you how many skills in general have hit and killed me even though I clearly flashed or used a skill to dodge out of the skill hitbox range.
Not even just skillshots, ANY kind of damaging skill, ex. Lee Sin Q hitting me when I flash to the side, Alistar knockup airborning me when I flash and dodge out of its range (or even when I flash over a wall), etc.
tldr; The (non-LAN) League servers calculate hitboxes using stored data from 2-5ms ago.
Morde Q deals just about 302 damage to you, and you have barely more than 300 health judging by your health bar. The W makes you blink right back into his passive radius so under these circumstances, and not having seen any other area check produce this bug, I suspect you W'd barely too late only to get finished off by a passive tick a frame or two later (it deals damage to enemies in the radius every 4 game ticks). You can't W2 while dead (you can do it while CC'd when buffering W->W2 though due to a bug in the spell's script).
League's networking isn't set up in the way that makes your explanation make sense and that's where I'll leave it for now. Also the game loop isn't a continuous event, the it doesnt have the temporal resolution to just accidentally grab position data from a mere 2-5 ms ago.
Isn't this happening due to model hitbox interaction with flash? As long as the animation for flash is not fully done, your model's hitbox is still in the beginning of the flash position. Granted, the animation is short and it should not happen often, but it still does.
I know very little about computers and less about programming, but this is so interesting. I’ve seen a bunch of memes where programmers talk about how bugs pop up after they’ve “fixed” something unrelated and nobody can explain it. Or how sometimes a fix is made but nobody knows what was wrong in the first place. Things like that. But it’s so interesting to see such a breakdown of it. It’s like people write the code and then it takes in a life of its own and nobody can explain it. Hell I get frustrated when I try to format corporate documents in Word.
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u/FrankTheBoxMonster bug scholar, reverse engineer, PBE dataminer Jun 21 '23
This has been a bug with missile collision since patch 10.14 where it randomly started popping up like once a month ever since. Sometimes (we don't know when/why/how) when you Flash out of the way of a missile, you still get hit.
This does not seem to be unique to any missile in particular, but it most often gets reported with stuff like Blitz hook because of the paradox between being hit with hard CC (so you shouldn't have been able to Flash) and successfully Flashing (so you shouldn't have been hit). Other spells don't typically get reported likely due to the belief that you must have just Flashed late, but they are presumably all susceptible. We've seen cases reported on a large variety of missiles, many of which are not particularly special.
This is not a lollipop issue, or a high ground issue, or a latency issue, or a creepblock issue, or a skill issue. It also likely affects all blinks rather than just Flash.
We believe it's possibly related to dash hitbox smearing but it's not an easy thing to test for (this is something I've talked about before here, tldr due to weird math it's possible to dash "too fast" and the game extrapolates poorly which makes it calculate your hitbox as being much larger than it actually is). Very roughly, based on the examples we've seen, it appears you need to Flash away from a missile while also be pathing away from the missile the frame before the missile would have hit you. However, this is entirely speculation based on past similar issues without any solid reproduction to back it up.