sacrifice at midnight

I got a ton of Midnights running the lab from the chests at the end. I havent gotten any from Vaal Side areas and got 1 from the "her mask" div cards.

midnights have a drop restriction is why you usually have far more of one than the other, most common plebs like me get their fragments from leveling alts etc and you can't get midnights until 60 i think

From a game design perspective, I'd say the reason Midnight (and hope) are much rarer then other fragments is to encourage fragment usage in the map device for quant boosting maps.

I doubt the intent was to gate access to Atziri/Uber Atziri. If that was the goal, the same throttling of access could have been easier achieved by making all fragments equal drop rate, but reducing the drop rate of fragments overall.

But back when Atziri and Uber Atz where first introduced, there was probably a concern that they would only be used exclusively to access those encounters. It's less of an issue now that the content is so out dated, but by making one fragment a rare bottleneck, it causes a stockpiling of the other 3 fragments, which encourages their use for alternative purposes (map enhancement). Now days of course I'd be willing to bet that far more fragments get consumed to add quant to maps then to fight atziri.

Or I could easily be completely off and encouraging map usage was never the intent of the rare fragments, and GGG just wanted to make one fragment of each tier to feel special, to make players have a moment of 'yay' when they get the rare one. Or even more likely, it was both.

IN the beginning, midnight fragments were way more rare than the others (1 of 100?) with noons at 2nd 'place'. Some time ago, it was changed to be nearly equal for both, but still a lot less then the other two.

Now with Incursion, they also changed the loot of the vaal zones to be much more rewarding - especially with the elimination of the previous limit to just ONE vaal gem OR fragment. I'm not 100% sure if the old limit based on the area the vaal zone is based in (part 1/part 2) is still counting, but I guess its not (early on you got nearly only gems, later it shifted to (more) fragments)

Now I nearly always got at least ONE gem AND one fragment, often multiple of one kind. In final I got 15 midnights (mainly from farming blood aqueduct, and some 'vaal maps'), this is a LOT compared to what I've stacked in standard over the whole previous time...

I don't know what the drop rate for it is but I pretty much always get at least 1 in Vaults of Atziri. The map itself is worth as much as the Sacrifice piece.