Dusk Diver 2

Story-related and cannot be missed.

This trophy is for completing Chapter 4, "Indicator", which you'll get once you return to the Tumaz Mart after defeating this Chapter's final boss. This Chapter is extra important because it unlocks two important features in the game: the Ritual and the Dragon Vein Shards collectibles.

You'll start off this Chapter by meeting a loud-mouthed, over-protective (and likely to become a fan-favorite) friend of Le Viada's, named Ull. Meanwhile, Boss sends you out on yet another errand, masked as a quest.

As part of Boss's errand quest, you'll finally unlock the Tianhou Temple's special "Ritual" feature. It's a Possessed locator system, which you can use once per chapter, that marks the location of all of the "special" Possesseds (tougher enemies that drop more and better items) on your map. (See The Evil Within  for more information about the Possessed and the locator system.)

Later on, you'll briefly revisit Civic Boulevard and will meet Bo Yin, Bette's mentor. This unlocks the Dragon Vein Shards, which are collectibles spread through nearly every location in Youshanding. If you played the first Dusk Diver, you'll recognize these right away. This time though, you won't find them in the Human Realm. Additionally, they're technically part of a Collection Quest called "Bo Yin's Dragon Vein Shards", so every 10 Shards you collect, you can hand them in to Bo Yin for a reward. There are 100 Dragon Vein Shards in total, and you'll need to collect all of them for the More Precious Than Diamonds  trophy. (See said trophy for more information and a location list.)
 

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IMPORTANT NOTE: After you finally meet Bo Yin, free exploration unlocks for several areas, allowing you to revisit them and collect each area's Shards. However, complete free exploration AND the second collectable type (Outfit Designs) do not unlock until next Chapter, so it might be better to wait until you do Chapter 5 to begin any collectible collection runs, so that you can collect both at once, rather than needing to return multiple times.

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As for the main bulk of this Chapter's story battles, you will visit and unlock yet another new location, the SCCP Control Area (Youshanding). This location's special mechanic is using something called "Meng Zhang's mysterious device" – You'll see a large blue or yellow energy field spread over a large wall on the side of certain buildings. Interacting with it will move buildings out of the way or into a different configuration, thus opening and closing various routes. It can be a little frustrating if you get turned around, but it's actually really simple if you understand that all you'll have to do is interact with each gate once, and that will take you straight to the end.

BOSS FIGHT: "UNKNOWN DEFENSE WEAPON"
The fight at the end is just a standard elite-level enemy-boss fight, against a machine called the "Unknown Defense Weapon". This machine somewhat resembles a spider, but with 4 legs. To defeat it, you'll need to destroy each leg. It's simple enough. It has 3 main attacks: it shoots missiles, it spins like mad as it goes toward you, and it can jump up in the air and then land on top of you. The latter is telegraphed ahead of time though, so it shouldn't be a problem; a couple seconds before it lands, it displays a red square on the ground to show exactly where it will fall. For the most part, just be wary of it when it spins, and you should be fine. One small tip is that you can use Bahet to attack multiple legs at once, and if you can reach Yumo's Burst Ultimate, it will also take out a good chunk from all of the legs if you position yourself well.