*WARNING - THE FOLLOWING BLOG POST CAN SPOIL A VERY PLEASANT SURPRISE OCCURING DURING THE ALERT*
As you might have noticed, there is currently (about 15 hours still remain as of the time of this blog was written) a semi-tactical alert with the title Proxy Revolt (or something like that, I already completed it and can't check), which offers an Orokin Catalyst as its reward. That by itself is pretty sweet, but it's not the only thing in which it is special.
Apart from the potato, the alert also runs for twenty Defense waves instead of usual ten, and has some uncommon enemies mixed into it. The first ones are Oxium Ospreys, which spawn extremely frequently and allow you to get about a thousand Oxium just by playing the alert. Second ones are Hyenas, which spawn here, about two in each wave. While the actual alert starts at level 10 and moves to about level 25 at the last wave, the Hyenas linger around level 45, so they can be a rather formidable threat for an unprepared Tenno.
The last and most interesting enemy that spawns here are Bursas. Usually two per waves, just as with the Hyenas, they drop the priced and amazing Tempo Royale stance mod, which is truly awesome and worth using. These Bursas are mostly around level 25 and spawn in the second half of the alert, aka the last ten waves. Make sure to bring your Nekros to get the stance, as the mission is not replayable once it's finished. (It can be soloed rather easily with proper gear, though, so you can just try and quit, over and over, until the mod finally drops.
For now, this is all, I simply wished to let you know that this one-time chance to get some sweet drops exists right now.
See you another time, Tenno,