I already lost track how many times this happened to me. I usually go with my paladin to fight Thunderwings. I go there, invite people to a party and we kill the boss. Everybody drops a stone of chaos but me.
I’m not AFK or anything. I’m hitting the boss, I’m buffing the party, using shields, etc but none of that matters apparently.
doesnt drop if youre below 1445
Hello @Alloc
I hope yo are doing well.
I’m sorry for the issue regarding the Stone of Chaos.
The information provided by @NyxSidus is correct and your character needs to have a minimum item level of 1445 in order to receive the Stone of Chaos from the Legion Raid.
Thanks a lot @NyxSidus for helping a fellow Arkesian.
I hope this helps. Cheers! 
This isn’t the case, I’m at item level 1490.
This isn’t the case, my character is item level 1490. I’ve been doing Thunderwings since the release, and I was 1445 way before the field boss was available.
Thanks a lot for the additional information @Alloc
In this case, I request you to submit a Web Ticket to our Support Staff using the below mentioned link along with the link to this thread to escalate the issue further.
See you in Arkesia. 