When this happens on a location, the investigator is drawn through gate and delayed (that is clear in rules).
Since this was Arkham Encounters does that mean another encounter same turn in Other World Encounters (meaning overall they have 3)?
As I understand it the purposed of delaying investigators sucked through (mechanically) is to ensure they have 2 otherworld encounters, so I assume they don't have another encounter.
(Yig's luck holding out, 1st turn and 2 different Arkham Encounters open 2 gates on investigators, turn track ends at 4 end of Turn 1).
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? I would think he/it changes the focus on which gates to seal, that is low-priority are better than med- or high-priority. With Y'ha-nthlei having 2 Mythos cards that open a gate on it, only seals safer are via Great Seal or Naacaal Key (latter assuming you can open a gate at a stable location).