Yes you have to play in torment. but as someone who could only manage mp1-2 Id say the drop rates are already much higher on T1 as I managed to get both a key and the infernal machine plans from the same kill. I almost always get a key between 2-6 runs. I could do 20 in MP1-2 and not find more than 1 key and never found the plans.
T1 is 25%, T2 - 28% ... T6 - 50% of drop chance. So doing key runs on T1 can take some time if you are unlucky
But it might be "more efficient" than running T6. Doing 100 runs on T6 you will find 50 keys on average, while on 100 T1 runs you will find about 25 keys; but those T6 runs are waaaaay slower than T1 runs (not just 50% slower). So for pure "key farming efficiency", you might wanna choose the Torment level where you can easily breeze through mobs. No necessity to go all highest difficulty anymore, as in D3V with MP10. Same for ubers.
The most disappointing thing is when you get several dozen keys to make several runs at ubers and get NO organs XD and T1 is really you can manage (stupid smarter Wardens, Curse you Odeg lol). It makes you wanna cry. All I want is one damned hellfire ring game is that so much to ask?!
Do I have to play in Torment to get them to drop or what?
I'm glad that I won't be trying to run Master for the keys
The season is underway. Don't know if I'll make it through.
Akarat save me !
I like these new numbers :-)