Numerous people have been asking me questions regarding these chests, I wasn't able to answer the majority of them, so I decided to make this a learning experience for myself & others.
Big shoutout to Mhk for helping with this guide & Omicron for the info!
Requirements
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Risked wealth of 1M.
Level 95 combat.
Opening the chest
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First person to loot the chest gets the items, after which the chest disappears within a few minutes.
Upon looting the chest:
You will be White Skulled (items lost on death, possibility to protect)
You will be Teleblocked for 2 mins & 30 seconds , This will not be removed on logout only way to lose the Teleblock is: wait out the timer or leave the wilderness.
A yell announcement will be put out.
Visualisation:
Video:
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Locations
A broadcast & chatbox message indicating the location will be put out 3 minutes before the spawn of the chest, for example:
NOTE: THE GRAVES & DARK CASTLE LOCATIONS ARE THE SAME
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Red writing indicates the broadcast message & red circle shows the locations.
Lootations
The most common drops are random combinations of bolts, pots & food. Less commonly, we may also see (in descending order of frequency):