Devs, could you add some guaranteed Mastery points or trophies to these WBs?
After you get T2, there's little incentive to kill the WB. I've killed 50+ WBs and never gotten a relic, trophy or T3 drop... so I know that these "rare" drops are ridiculously rare. And I might have gotten a Mastery urn like once. Not enough incentive for me to keep going.
As for the legendary cloak - it's good but not great. Sure I'll kill one WB a month. But that's about it.
What would keep me killing the WB continuously (and this is good for everyone because then I'm going to be helping other lower-geared toons out) would be some Mastery points to help with AAs. At least 250k. And some trophies. Or better chance to get a T3+ drop.
As it stands, I can get 250k Mastery and 8 rares from solo unchained in less than 30 minutes.
WB takes at least that long to kill, and usually longer. Then you have to wait around for 30 minutes for a respawn. So figure at least 1 hour and maybe 2 per boss kill (took 2 hours last night - couldn't fill the raid). Let's see ... spend 1-2 hours and get (probably) nothing, or go do a dungeon raid and get tons of mastery and relics, guaranteed. Hmm. Tough choice.
Devs, please tweak boss rewards.