So just to update because I'm stubborn, did another Ameretat, putting me at 5 kills now (maybe 4)
9 vines (1 char has both drops, so 11 vines), 1 mask putting me at
3 masks (and none of them are on one of the 2 the chars that has the lotto pop body)
2 leggings
By char:
neither
mask
neither
mask
both
leggings
This is not worth it lol. I'm giving it an honest *** effort here, double dipping every kill with a key, but giving personal loot tied behind a ***drop rate is ***. Noobs would be better off doing Omen for cards and gil or Ambuscade for freebies (total HM) and gil. They could have added an actual loot pool on the NM as well for that drop that is being stubborn.
Dumb as it may sound, I've had a much worse drop rate...
What I would do is warp to Morimar #4, mount over to and kill PH's for the Matamata that no one was camping, then warp, and weypoint to an 18 minute NM. I'd get about 5 NM's in a cycle before the 1st NM respawned.
In 3.5 hours the Matamata finally spawned, and I had killed each timed NM about 12-13 times, so we're talking 60~65 kills. Of those kills I got 2 pieces of armor, and not from the 3.5hr repop lottery NM.
And yes I'd grab a new key daily, so there's a few additional drops included in that mix.
The drop rates are really bad, but that's how they want the content. Their solution to keeping players playing is to keep drop rates low. That's what they did with Limbus. They can't fathom that someone would enjoy playing the game without chasing an item, or that if someone took a break to play another game that they would consider coming back. It's not the best mentality but that's the hand we're dealt.
I think the best solution for this content would be to remove the Rare tag from the key and make them stackable, and change NOTHING else. Let players buy and stack keys each game day here and there over a week or so at their leisure while doing other tasks and content, and then when they decide "hey lets camp this NM", when it pops they can throw as many keys at it as they want.