Originally posted by Shaken_Widow:

the above comments don't truly do it justice.

the game uses a heat system for your base rating.

basically, you have items that can prevent raids that you can place, but they can also add to the chance of spawning a raid if there are too many too close together.

and then you have what i call the grudge rating which is basically actions you do throughout the world that anger the mobs, from cutting trees down to killing creatures in each location, all different things anger the mobs and add to the chance.

so you have your base rating, your grudge rating, and THEN it's RNG based off of those variables.

im pretty sure there's also a boss timer that plays a role as well, as well as a grace period for both the start of a world and after each raid.

this is nearly ALL wrong information and should be removed to avoid spreading missinformation around.

there is no HEAT system. at all.

the 2nd sentence is also nearly fully false. you cannot prevent raids from occuring with items you place at all. unless you cover an area that is SILLY large with them to block all spawn points within LOADING RANGE which is a massive area. and even then you would STILL get the red circle to appear.

the grudge ratieng doesnt exist. purely madeup part.

this is whats actually the case :

a raid event can only occur if there is a any PLAYER within loading range of atleast THREE player BASE STRUCTURES. if there is no player in loading range no raid can occur.

these are all player structures : anything not listed here does not count as a player base structure and has no impact on raids occuring or not :

https://valheim.fandom.com/wiki/Player_base

if 3 of these close enough to each other a raid event can occur once every 46 real time minutes with a 20% chance. this chance NEVER increases. so its totally possible to not see a raid event for 30 days in a row. as its purely rng as you can see. you could also get 3 in a row if unlucky.

if there is only 2 or less of the above link listed structures no raid events can occur at all. thus youll never see them.

EXCEPTION :

"you are beeing hunted"

this can spawn ANYWHERE regardless of the above conditions aside the timer part aslong as the player is within a mountain or plains biome. thats the ONLY event so far where this is the case. this event CANNOT happen until you KILL bonemass. BONEMASS ONLY. other bosses dont matter for it to occur.

this event only needs any player to be anywhere within these biomes to have a chance to spawn. can happen even while fighting moder or yagluth.

raid event "progression" is based entirely on BOSS KILLS. KILLS. not hanging the trophy at the stones.
some events are triggered by 1 boss beeing killed and turned off permanently again after the next boss is in the "normal" order is slain.

https://valheim.fandom.com/wiki/Events

you can see which boss triggers which event and when it stops (if nothing is listed on "disabled by" it keeps happening for good once the "enabled by" condition it is meet in a world)


some events have multiple requirements before they occur. some can only occur in certain biomes. like trolls will attack base after elder is slain but ONLY if also atleast 1 troll was killed aswell (the troll does NOT have to be killed by the player to count. the world simply checks for a troll kill on the internal counter so if a mosquito or lox killed a troll it does count for the trigger condition) but chopping trees or mineing resources never has any impact on raids.

but nearly anything quoted poster has said is false or simply incorrect information. thus please ignore it.