maybe a 1.2% chance but honestly, I think you're undermining the difficulty in getting them if you think it's "all failed boxes for 8 hours." I open probably 95% of the boxes I find, and usually that other 5% is a 4-chance chest with pointless hints until you get to 2. At 3 you could potentially break it down to a 4-digit run and then a this-or-that run and then succeed, but at 2 you'll almost always have a 50/50 with those kinds of boxes. Does that happen often? No. Is that *always* the difficult-to-obtain treasure? No. The fact is that some people report going 1/250 on these boxes, so whether or not you fail to open 10,000 times during that is completely arbitrary -- the thing was only ever gonna be in 1 of those 250 boxes, regardless of the order in which you succeeded or failed. That's how droprate works, yes? NOT killing a mob nets you no treasure in the same way as NOT opening the chest: it can't be recorded for drop data. If I kill 2,000 mobs and maybe 30% total drop brown caskets and I choose to walk right by and not open them, those don't count as "I didn't get it."