Any tips out there yet

Kill and loot a lot of stuff, it's a small percentage drop chance, the more loot you get, the more chances you get at one.

Dungeons and world quests..

rng

farm heroic dungeons probably

I farmed a lot of heroic dungeons and got a legendary off an emissary chest, idk what you can make of that but yea

Iirc the only way to get them at the moment is through the world quest chests.

Any and all dungeon bosses can drop them, also mythic dungeon bosses have significantly higher chance to drop.

Emissary Cache also drops ofc

which world chest?