I just burned 15 imps on the same assignment back to back. First time on this assignment. I didn't rank up anything. I didn't rank up at the fame NPC either (Still: "I remember your name, but I forget why").
KI dropped to 95k. Ranks are still Scout's Disciple, Pioneer's Contributer, Peacekeepers Petitioners, Rest completely untouched.
So going from 121-123 to 136-138 Imps spent and 3 different completed assignments to 4 by spamming the same coalition assignment for all 15 tags resulted in KI dropping from 100k>95k. Only other thing that changed since I last checked KI price was getting a 2nd Delve Mega Boss KI.
So it's obviously not 5k per completed coelition otherwise I would have gotten it before I started ranking up Scout's. 3>4 assignments and 120ish>135ish imps seem like a really wierd boundry line for a KI price drop.
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