#overthinking this

What is he doing on that raft?

Why do the refugees leave the Southlands on a ship? The Southlanders we get to know in the show are farmers mostly, what drove them to sail out on the open sea? Was their aim to seek the protection of Númenor, and if yes, why set out on the sea and not first, for instance, to the town (?) of Pelargir, which Bronwyn mentions as a Númenorian colony already in existence (ep. 7), why not flee there? Or why not go to Ostirith and tell the Elves about what happened?

In Númenor Halbrand tells Míriel, Pharazon and Galadriel about where he's last seen the Orcs and it looks suspiciously like the village Hordern north of Tirharad (if the little marker there on the map is supposed to indicate the place where Halbrand stayed last). But none of the surviving Southlanders after the battle or in the camp recognize him. They come from all parts of the Southlands: in episode 4 inhabitants of "every village from here to Orodruin" (Bronwyn) seek shelter in the deserted watchtower. By that time however, it's been weeks maybe even months since the party on the ship, including Halbrand supposedly, set sail and perished.

Woman (to Galadriel): We set out two weeks ago, sailing -

Man: Need we tell her all our affairs?

And do the shipwrecked even realize they're adrift that far west on the sea? Are these Southlanders from another part of the Southlands? Are they Southlanders at all, or maybe from Rhovanion, or Harad? Halbrand could tell Galadriel anything…

Was he really in the Southlands/future Mordor at all? Why would he follow Adar and the Orcs there? He knew what the plan was. If Halbrand was there and did something, anything, Adar didn't notice because he's obviously a stranger to him when they meet, as well as to the villagers.

The origin of 'Halbrand'...

Adar kills Sauron in the north, then marches with his Orcs southward - "From Ered Mithrin to the Ephel Arnen we have endured" (ep.6) - and starts digging. This takes a while but not too long, given how fast the Orc attacks on the villages progress in the show. Adar doesn't waste time. What did Sauron do in the meantime?

He was a disembodied spirit after Adar "split him open". When it happens to him at a later point in time he needs considerable time to create (or whatever) a new body for himself and then it's not the "fair form" he used to have. This time he's immediately reincarnated, and beautifully. How so?

Reincarnation/reembodiment technicalities

I suppose there isn't a call to Mandos for a Maia as there is with Elves and Men. Technically he's not an unhoused soul. He's a spirit by nature.

Reincarnation is Elves-only business and it means being reborn, a new start from the scratch. Sauron didn't start out as baby Halbrand who growing up remembers he once was Sauron, servant of the Dark Lord.. Yay! It surely doesn't take Adar about 30 years to make Mordor happen.

Furthermore Sauron canonically avoids a return to Valinor after Morgoth's defeat. It's unlikely he returns to the dwelling of the gods he so fears to ask for a new body and then runs from their judgement.

Quick stint to Valinor?

I mean, sure he can go this way. And maybe getting back to a physical form in Valinor works differently for Maiar. And maybe he lies to the gods a little and then steals away from Valinor.

He can also reject the call if there is one. When he's disembodied after Númenor's downfall and a second time after the Battle of the Last Alliance he doesn't go to Aman either.

Halbrand tells Galadriel on the raft:

"When Morgoth was defeated, it was as if a great, clenched fist had released its grasp from my neck. And in the stillness of that first sunrise, at last, I felt the light of The One again. And I knew if ever I was to be forgiven... That I had to heal everything I had helped ruin."

This sounds like ROP goes with canon that he evaded judgement, but thought he could repent on his own. Adar has told Galadriel a similar story about Sauron. Maybe Adar thought: 'If you want to redeem yourself, just eff to Valinor already and face the gods instead of cowering here in the cold, sacrificing my children for your sorcery. I'm doing you a favour now.' Yet everything Sauron tells Galadriel happened before Adar killed him. And now revenge is all that's on his mind, and he's relapsed already.

Does Sauron really go to Aman and then squirms himself free of his sentence and of the long "test of his good faith" and somewhow returns to ME calling himself Halbrand the Southlander, crafts himself this sigil, maybe puts a magic spell on it, waits to find people stupid/desperate enough to recognize the long lost heir to the crown in him to... to what end? Driving Adar out with an army? Pretending to be royal to have access to upper society in Númenor to corrupt them? Both?

Is Halbrand the default option for Mairon?

Anyway, he does get back to a physical form. And he does it fast.

It's being speculated that Halbrand is Sauron's Mairon form, but what about Adar? Adar is so old, he's possibly one of those Elves who awoke in Cuiviénen. He knows Sauron's physical form well. If he doesnt recognize Halbrand, but Halbrand is Mairon's original form, then Sauron must've changed his form/body even before Adar got to know him and then he stayed unlike that original form for thousands of years. How often do Maiar change form in ME? Do they always return to the same form, like Gandalf (in ME at least) seems to be Gandalfy, whether grey or white…

If Sauron's form changed every couple of years in unrecognizable ways, I think Adar would've been more alerted when that angry guy pinned him to the ground and wanted to be remembered by him.

Is Halbrand some guy that Sauron thought attractive enough to try on?

Is Halbrand maybe some doomed guy who had to give over his body to Sauron because of a blood oath or something. Sauron is a necromancer. Maybe he can steal bodies.

In Númenor he's got to say this about the sign on his pouch:

That's funny. I found this on a dead man. Thought the pattern suited me.

Be careful, Elf. The heir to that mark is heir to more than just nobility. For it was his ancestor who swore a blood oath to Morgoth. I am not the hero you seek. For it was my family who lost the war.

Okay, given that he's always telling the truth somehow, one can assume he took it from a dead man. Interestingly he changes person when he elaborates. "The heir to that mark" is someone different, not him.

Another interesting aspect is that he speaks of family. He doesn't use 3rd person here. Morgoth, the "clenched fist" around his neck - does Halron really describe him as family? Does being bound by a blood oath constitute familial ties? He talks very much like Adar.

Miscellaneous...

Why is Galadriel immediately convinced she's talking to the lost heir of Southlands royalty because of this pouch, but the Southlanders on the raft are acting rather indifferent to him, like 'who dat?'. Bronwyn is literally melting when she spotted the sigil of the "king we were promised".

Was he on his way to Númenor trying to do what he will do later? Maybe he wanted to make rings there. What was in his pouch anyway?