Manpower99
commented
3 days ago it is quite noticable that if you summon a hunter/lock into vezax while skipped a couple of mobs, the pets somehow dont get summoned with you but rather clip through wall and pull those trashmobs. idk if they should do it by server render distance though. but i believe certain trash events such as snow mounds just put everyone in combat instead of only those who are nearby and/or the guy who triggered it, likely causing one of the major issues of a usually skippable trashpack/trash event.
Piootrek
Description: I've noticed most of Ulduar combat bugs recently stemming from this issue. Basically if the group gets in combat with trash and wipes while someone from the group is alive elsewhere or one person skips while the main group wipes (any situation where the group is in split location). The trash might aggro someone far away and goes through walls/floor/map to follow them. At this point if you don't convince 10/25 people to wipe all at once, you will have combat bug until 30minutes later when mobs magically appear from under the map to attack you. Even if the person having combat from this removes combat it seems because the mob is targeting from out of bounds he is technically still in combat. For example, I used vanish as a rogue and a paladin gained combat from single target buffing me after.
How to reproduce: This is most prevalent with pre-mimiron and pre-hodir trash(snow mound worms) as they pulsate some weird combat on group when engaged, but the way this works could potentially be any trash.
How it should work: Bug probably caused by a combination of 2 things:
Mobs should follow terrain pathing instead of going through walls, if the target they are after is not reachable through standard terrain pathing - mobs should drop combat, evade. and go back to their spot after a few seconds.
On this server mobs behave weirdly(or don't behave at all) when beyond server render distance, at least when it comes to pathing (this can be seen with Patchwerk not even starting his patrol until a player sees him for the first time) - I believe this is why mobs randomly pop up after 30minutes because players are circulating around, sometimes close enough to the spot where mobs are beneath the map allowing them to "exist" and slowly move towards the group. Perhaps a rule like this should be applied: instanced mobs that are engaged in combat should drop combat if beyond server render distance of any player.
Addressing any/both of these will probably fix this issue, although I believe 1. would be enough for this not to happen anymore.
EXP: Example from personal experiences:
Random 25man, someone accidentally spawns snow mound worms as they do causing a partial wipe. We try to use teleporter to remove combat but not everyone listens since random group, end up clearing trash, hodir, and waiting at thorim for a GM to clear combat bug for us. Waiting at thorim entrance 20-30 minutes after snow mound was pulled, worms sprout from the ground and killing them removed combat from everyone.
Random 10man, tank skips mimiron trash while rest of the group wiped on it. I used vanish and personally watched the mobs go through walls to go for the tank that was already at mimiron. We never had these pop up randomly as we decided to wipe after not getting rid of combat. DBM timers were messed up for the rest of the run, every boss wipe did not count as a wipe and timers kept rolling while dead until /reload.