Vol’jin fused with a Loa in Shadowlands. 
The Amani tribe haven been fusing with local Loa. 
Rumored to be the most feared witch doctor of the Amani tribe in decades, Hex Lord Malacrass has done the unthinkable and sealed the essences of several mighty troll animal gods in their strongest champions … keeping the darkest one for himself.
Still mad Rezan died.
Wishful they do this justice. Assuming Vol’jin with a light Loa and Hex Lord with a dark Loa would be fighting. 
What dark loa was her trying to merge with? This is really interesting.
It’s funny but the Zul’aman Loa weren’t named although we’ve encountered them about four times. 
…although the suspect is either Kith’ix since it slumbers under Zul’Aman or a Dreadlord since he’s partnered with demons. 
https://wowpedia.fandom.com/wiki/Kith%27ix
I always been curious if the C’thraxi, ones like Kithix are somehow immortal
Every sufficiently powerful one we come across was either buried somewhere in a slumbering state, or thought to be killed only to reawaken thousands of years later to wreck havoc
The most powerful of the Old Gods’ servants seem to inherit some of their master’s nature as being “outside the cycle” of normal life and death. What should kill them just renders them dormant until someone either destroys them completely or wakes them up.
Especially the C’thraxxi, which are extremely powerful faceless ones, and of the Old Gods’ servants the n’raqi come across more like sapient appendages of their masters’ wills than a race of fully realized individuals.
They can perish and go into the plane of Ny’alotha although some still create whispers to influence their return. Likely they don’t care about death. 
https://wowpedia.fandom.com/wiki/Soggoth_the_Slitherer
edit: I think this is something related to Cthulhu in which the sailor impaled the creature’s head with his boat but we’re told it went to sleep. 
Didn’t Sethraliss sacrifice herself to put one to sleep? Mithrax or Kith’ix?
She sacrificed herself to kill Mythrak. Her devoted followers would transport her remains and eventually built a temple around said remains, and waited until her eventual rebirth during the events of BfA
Mythrak was ultimately revived too and destroyed the final disc in Zuldazar that was keeping G’huun prisoner
They had teased already that he’s coming back as a Loa. They just haven’t completed that story.
Sethraliss was revived by the Horde PC. So Vorrik owes us.
I’d argue Baine is at least ‘new blood’ of the Horde – but lets be real, he’s more of a new blood generation for the Alliance than the Horde 
At the very least we have Talanji.
“Bring me the head of the Proudmoore witch – Avenge my father!”
Vol’jin getting his ‘loa’ ordeal of what made him special from Rezan kind of ruined the awe of him rising to become a loa in his own right 
… It’d be cool if he used that ‘spark’ of Rezan to revive him against all odds & knowledge of what seemed possible, and through such actions elevate his own individual spark in the process.
There is no worse feeling then getting attached to characters only to see them being deleted shortly after just because Blizzard is too incompetent to not make the Horde villains every 5 minutes.
“Garrosh is the new blood of the orcs? Tsssk we really need a new villain … {rubs villain-bat romantically} … Lets beat Garrosh with this.” 
( A few expansions later )
"Yo we need another new villain? What do you mean, the Horde are literally right there. Yeah I main Alliance, but that’s irrelevant – Look, that Sylvanas has always been villainous, lets just put the pedal to the metal and use our famed beloved villain bat on the face of her character so hard & brutally, that she’s barely recognisable by her loyal fans 
"
I mean the only new blood characters would be thralls kids and that one belf orphan who grew up, everyone else just has no characters who could fill that niche
Yes Blizzard did a splendig job at removing everyone who ever had an ounce of character progression.
Wouldn’t surprise me at all if Gallywix had dozens of illegitimate children running around. Can’t say the same thing about Gazlowe.
Sylvanas was undead so… can’t see how she or any of the Forsaken could even have offspring.
Vol’jin had a son. We don’t talk about Yenniku.
Baine was Cairne’s son, but had yet to have a child of his own. Mayla is in a similar boat where she was the prominent child who rose to power after her father’s death.
Lor’themar only recently found someone to have a child with, same as Thalyssra.
We have no lore about Kiro having any children. Blizzard could always make them appear from nowhere, I suppose, since we have no information about Vulpera customs in those matters.
Talanji herself was the child of a leader, so again, no chance to have children of her own yet.
Geya’rah follows that same line of thought. Thrall does have his own children of course.
So, yeah, looking at it more closely, it seems the Horde already is mostly at that point where the Second Generation has come into power. Baine, Mayla, Talanji, Geya’rah… Four individuals who would’ve been the, ‘next generation,’ and rose when the old guard died off.
Yes while the alliance still has their second war leaders with their own kids the Horde leaders are just cheap replacements for characters that were much better then what we have now.
Which is bad and bias.