Found this set awkward to complete at first but a good tip is to set your camera angle from above you, high above. That makes it easier to spot the ones that hide in the shrubs round the buildings. There also turned out to be quite a few hidden high in the eaves of the buildings and the upper ledges.
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Chard ~ 115 Magician of Bertoxxulous Mean Ole Men Formerly a soloer but now twin boxing another mage.
You can get these achievement done in under an hour. Invis up, Draw a box from the western edge of the disappearing wall, down to the debauched noble, east to the aqueduct drop down, and then north. Most of them will be found outside. Be sure you are lev'ed, because a lot of them will spawn up the side of the houses. Spend most of your time outside, going in the 5-6 buildings after exhausting the outdoors.
You got extremely lucky if you got all of these in under an hour. I've been running around for over 5 hours and still missing 3 collectibles from this zone.
in the canal district A ( central northern area and a bit east), also inside and outside the building where the possessed farseer spawns (shissar thugs inside on 1st floor). also outside the building just north of there and inside the building east of that one ( loc 2460 x -570 x 325).