Sacrarium Chest Key  

This is used to get the map of the Sacrarium. You need to activate the quest first by talking with the NPC Nivorajean at I-9 in Tavnazian Safehold. He's just to the left of the rope bridge on the level of the Safehold you enter on.

You have to be on CoP Mission 4:3 to activate this quest and you also have to have entered the Sacrarium at least once. When you very first enter you get a cut-scene for 4:3 and after this you can then later talk to the NPC to activate the map quest. I did try before entering the Sacrarium (even though I was on 4:3) but he doesn't give the quest till you've been there once.

There are eight possible pop points for the chest and seven of them can be reached solo. There is one pop point that is behind the door that needs the Sealion Crest Key and also a Coral Crest key to open. So to reach that point (H-9) needs at least two people, each holding one of those keys mentioned.

The other pop points are F-5 H-5 F-11 H-11 (these four are rooms full of Fomors. Need snk only)

Also at J-5 and J-10 (these are dead ends with Gazer mobs nearby. Again snk only but watch for the true-sight Taur mob patrolling each small area before entering these corridors.)

The last pop point you can reach solo is at L-8 in the big room where Keremet is. My chest was here but it was quite easy to get to. Just had to be a little patient and wait for the true-sight Taur mobs to move away. You also need snk up too for the bats here. The chest in this room pops very close to Keremet, but he never aggroed me at all. Was a little nervy though.... lol

I picked the lost on my THF but made sure to use as much +DEX and +INT gears as I could for level 50. I even popped a Squid Sushi before picking the lock for added +DEX. Once you recieve the Key Item of the floorplans return to the NPC and he tells you to wait a day while he makes the map.

At this point I'm not sure if it's a game day or a full RL day. But I have other stuff to do anyway so shall return another RL day.

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Probably requires some sort of quest or something to get an item from this chest. I got a whopping 6800gil :|