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hey genshiners,, there's a new event called "lost treasures" !! here's a mini thread of the locations of the iron coins 
first, go to dihua marsh and talk to "Ulman". he will give u the treasure book and the seelie that u will use to find the iron coins
second, go to ur inventory, click on gadgets and equip the seelie.
third, check the treasure book. the first location is " falcon coast ". use the temple near to teleport there and use the gadget (click on it)
fourth , follow the shining/twinkling light that appears. most of these only appear during the day so make sure to take note of that.
location #1 : just near the entrance area
location #2 : near the children and the guard
location #3 : the big rock on the middlemost
location #4 : behind the big rock on the middlemost l
location #5 : near the big rock in locations #3 and #4
location #6 : northwest , in front of the big tree, near the estuary
location #7 : situated at the northmost part of the circle (my map is rotating)
location #8 : also near the estuary
location #9 : this one is near location #1 ,
(i just found this out but u possibly need less or more !! most locations give 8 iron coins but some give 4, some give 20 !!)
next area is lingju pass !! teleport there using the portable waypoint that is located just around the area. (note that most of these appear at night)
location #1 : in front of geo pillar, near the tree
location #2 : on the west side of the arc , left path
location #3 : west arc , in front of a geo pillar with a torch and pressure plate next to it.
location #4 : outside the ruins, southwest area.
location #5 : below the east side of the ruins. you can see two geo pillars here.
location #6 : east of stairway next to the statues
location #7 : east arc , adjacent to geo pillar and right in front of a windwheel
location #8 and location #9 : east arc , in front of explosive . other one is near the waterfall. (i alrd collected 60 iron coins so i didn't get to collect the last one.)
the next area will be unlocked in 11 hours, so for now stream oomf's childe fancam 
