This event never spawns, I've camped there for hours.
This bug is also reported on wiki (https://wiki.guildwars2.com/wiki/Clear_the_poisonous_urchins_from_Lashoosh) since september 2017, please fix it.
For more info: it's an event who should take place at Lashoosh, slightly east of Isenfall Waypoint in Snowden Drifts.
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