For this you will need a plate of some type and at least 2 Do not delete chests. Using a plate or platter press against the door leading towards the the deeper part of the Ratway at the rear of the Ragged Flagon and once you pass through it, face down and place a Do not delete chest below you to use as a platform. If done right you will be floating below the Ragged Flagon, standing atop your makeshift platform and from there you can alternately use your Do not delete chests to make your way towards the water, after that it is a matter of swimming to each of the six merchant chests hidden there under the Ragged Flagon.
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