Here's the map for 600AD, which is relevant because today's side quest takes place in this era.
The Black Omen hovers over where Magus's castle once stood. The time gate that occurred there must have taken the entire castle with it. So no going back there.
Immediately to the east though is a similar yet smaller structure.
Today we're going to tie up some loose ends with our good old friend Ozzie.
Magus isn't required for this one, but he has unique dialogue if he is around, so why not bring him?
Underground Sewer 
Look who's here to greet us.
Whoa!!
The nerve! Deserting your fellow Mystics to serve these humans! You're a traitor! You're not our King!
Then Ozzie does his what is most natural to him and runs away.
He doesn't run far, though.
Ooh! I'll have you begging for mercy.
Well, if it isn't Sir Magus. Who'd you bribe to get in here? Traitors like you deserve a beating.If Magus isn't here, Flea instead responds with the wonderful line, "You know, I REALLY don't like you."
I'm counting on you, Flea!
Battle 1 
Flea Plus is pretty easy. Measly 2500HP and average defenses. Her attacks are nothing to write home about, either. Mainly exists to slow you down.
Underground Sewer 
On to the next room...
You're nothing but common thieves!
The Japanese version specifies that this is treasure he stole from Magus's castle, which will be relevant soon enough.
But first, a battle.
...or not. When it comes to castle design, Ozzie is no Magus.
And here we go again.
Well, how about a good thrashing!
Slash, don't let me down! Battle 1 
Ready?Slash is a bit more remorseful to fight Magus in the Japanese version.
Same deal as Flea, only really here to slow us down.
And here we go yet again.
Underground Sewer 
Uh...no thanks.
Hmmmm...
Foiled once again. Though this means that treasure is free now...
Meh.
If we actually fell for the trap, the entire party would be knocked down to 1HP.
But this ain't the treasure Ozzie was talking about.
You see, there's a secret room over here.
Inside are a Doom Sickle, Gloom Helm, Gloom Cape, and a Magic Tab. The gear is all exclusive to Magus.
The Gloom Cape has no bonuses, but it's the third-best armor in the game after the sole Moon Armor piece and the ultimate armor that we'll see later. The Gloom Helm, on the other hand, is the second-best helmet defense-wise in the game (and we'll actually get the "best" one pretty soon), but with the bonuses of blocking status effects and giving +1 Speed.
The Doom Sickle is Magus's ultimate weapon, though in a normal situation it's still not too impressive. However, it does have a weird gimmick where it doubles in attack power if one ally is down, and triples if both allies are down. Of course, even in that situation you'd probably still be better off using Magus's magic, but still not too shabby.
And now we meet all three lackeys again.
Ozzie Pants! Flea Vest! Slasher 2!
Boss Battle 2 
Busting out the big music for this one. Their HP totals have beefed up, with Ozzie at 6000 and the other two over 4000. That doesn't sound so bad, but...
Each one of them has counter attacks. If you attack Ozzie, the group uses their own version of Crono/Marle/Lucca's Delta Force.
Attacking Slash triggers a Fire Sword counter.
And attacking Flea results in the Crono/Marle/Frog Arc Impulse knockoff.
They each throw in their own attacks, but it's the counters that will wear you down. And if you attack all three at once, enjoy eating three separate counters!
Remember those items they bragged about? You can steal them.
While this does some nasty damage, the resulting counters take out Ayla and Robo.
Which means IT'S TIME FOR DOOM.
It "only" does 1k damage, but that's enough to take out Slash.
If Ozzie goes down, the others do as well.
Underground Sewer 
And off he goes. Again.
Prevents Chaos. Meh.
Speaking of Chaos, those Ozzie Pants we got are actually the best defensive helmet in the game, buuuuut when wearing them that character starts the battle under Chaos and suffers HP sap. Plus they're implied to be his underpants, so why would you wear those on your head, anyway?
The other two items are at least somewhat useful. The Flea Vest (i.e. Flea's padded bra) gives a nice +12 Magic Defense, while the Slasher 2 has a decent 22% crit rate and is the third-best katana in the game, though since we already have the second-best Shiva Edge, it's kinda pointless here.
And at last, Ozzie has run out of places to run.
Magus flat-out says in the Japanese version he was using Ozzie to get power, presumably to get his revenge on Lavos. Of course, the only reason Janus wasn't killed as soon as he popped out of that time portal as a kid was so Ozzie could use his magic powers to fight the humans.
Of course, neither needs the other anymore, so...
Boss Battle 1 
Ozzie is once again doing his invincibility trick, and once again we've got switches to hit, so...
Go figure, Ozzie actually got one up on us for once.
Not that it's a long fall, of course. Just gotta go back up a screen.
He's right. We will never defeat Ozzie.
...You know what, let's just roll with it.
Anyway, that's it. You may figure that the only reason to do that dungeon is for the gear, but in case you haven't noticed, we've been changing history recently.
Delightful Spekkio 
The fall of Ozzie has changed history a good bit.
The Mystics aren't hostile anymore.
With Ozzie defeated and shamed, the Mystics lost the main person harboring a grudge against humanity. There's no such animosity anymore.
Ozzie's been exposed as a fraud, and his entire lineage suffers humiliation as a result.
Now human and Mystic relations have taken a bright turn, and 1000AD has turned from an age of quiet resentment to one where humans and Mystics are about to coexist peacefully.
The old shopkeeper who overcharged us is now replaced by a much more chill keep who gives us a nice discount.
Our actions have once again pointed to a bright, peaceful future.
Though we still have a long way to go until we ensure that such a future will extend a long, long time.
We'll continue working toward that goal next time.
