Fiery Warhorse's Reins

Funny thing happened to me today..

I had soloed Attumen for 2-3 months on a weekly basis for this mount, and today it dropped..
However I got the achievement, as soon as the mount was in my Inventory, and it had the blue text "You can transfer this to another character the next 2 hours" (or so)..

I wonder if multiple people could get the achievement this way (if I had not soloed the boss, ofc)...

Ok almost correct, you used the wrong way to get the correct percentage's although they are close to the correct value, they are still incorrect: For the Swift White Hawkstrider I will use 2% chance, the chance of getting one with 7 chances (1 per day) is found by finding the chance of not getting one and subtracting from 1. 0.98^7=0.868 > 1-0.868=0.132 or you have a 13.2% chance of getting a swift white hawkstrider with a weeks grinding. So I will make a table like you did: Swift White Hawkstrider = 13.2% per week (1-(0.98^7)) Fiery Warhorse's Reins = 0.7% per week Reins of the Raven Lord =

grrr, many years going by and I still can't get this mount to drop.