Interesting... maybe the silver voucher is the booby prize of booby prizes because I already had an imp box on my main.
I've opened seven rainbow boxes. Four Impish Box/Silver AMAN, three high tier drops.
1. Impish Box
2. Silver AMAN voucher (character already had an Impish Box)
3.
Crepuscular ring (character did not have an Impish Box)
4.
Cath Palug hammer (character did not have an Impish Box)
5. Impish Box
6. Impish Box
Gusgen chest key (huh??? This one is quite odd. Honestly I wasn't looking too close - should have been rainbow chest, but I almost wonder if I accidentally missed a day on this mule and this was the normal FES key? Will check again tomorrow to be sure. No impish box already on this character. Possibly also a re-roll for an item that character already had?) LOL yeah, came back the next day and somehow I must have missed a day on this mule - got rainbow box the following day, Impish Box.
7.
Crepuscular pebble (character did not have an Impish Box)
FWIW, #1,2,7 above were opened in Windurst Walls, and #3,4,5,6 were in Upper Jueno - though I doubt the zone matters.
Based on that Crepuscular Ring and Pebble, C.Palug Hammer, and Krizz's Composer's Mitts, versus lots of Impish Boxes/Silver vouchers... maybe this means that the stuff that is categorized as "common trash" from normal FES dial is replaced with an Impish Box (or Silver Voucher if that character already has an Impish Box)? But if you get a roll for "gear", which could be a higher rate like the event notes said, it's from a pool of high tiers/HELM stuff/etc.?
Another note, from a non-rainbow FES Key yesterday I did get a Niqmaddu Ring. Not too surprising seeing as how we'd already observed Ou drops, but I think that might be the first report of non-Ou Omen boss gear from this dial.
I'm also still finding it curious that we've seen several reports of the common Crepuscular/Null items, but none of the rare Shinryu ones or Null Masque. Would be very interesting if someone reports those drops.