You’re standing there in Citadelle des Morts, staring at a stone pedestal and wondering why on earth your fancy new blade isn't doing the cool light beam stuff yet. Look, we've all been there. The lion bastard sword upgrade—officially known as the Solais—is one of those "simple if you know, nightmare if you don't" quests in Black Ops 6 Zombies.
Honestly? Most players think you just pack-a-punch it and call it a day.
Nope. That’s how you end up getting cornered by a Mangler at round 35 with a toothpick in your hand. If you want the actual Wonder Weapon version of this thing, you have to follow a very specific, slightly annoying set of steps involving glowing bugs and a very particular door.
The First Step: Getting the Lion Bastard Sword
Before we even talk about the lion bastard sword upgrade, you actually need the base weapon. It’s sitting in the vault room, but you can’t just grab it.
You need a STAMP.
Wait until around round 10. A knight-zombie (the one with the bucket-looking iron helmet) will spawn. Kill him. He drops the stamp. You take that stamp back to the statue with the lion on its chest in the armory area. Put the stamp in, and the lion bastard sword is yours.
It's a decent melee weapon at first. It swings fast. It feels weighty. But compared to what it can become? It’s basically a butter knife.
How to Trigger the Lion Bastard Sword Upgrade
Okay, here is where everyone gets confused and starts running in circles. Once you have the sword, you'll notice these weird, glowing yellow parasites (they look like flying bugs) start spawning in.
Don't just shoot them with your gun. That's a waste.
You need to melee them with the sword. When you kill one with a melee strike, the sword itself starts to glow with a bright yellow aura. This is your "charge."
- Find the Lion Door: Head to the Village Ascent area, specifically the spot tucked away between the Well and Speed Cola.
- Smack the Door: Melee the door while your sword is glowing. A symbol will light up on the wood.
- Repeat: You have to do this four times. Kill a bug, run to the door, hit the door.
- The Teleport: Once all four symbols are lit, you can interact with the door to be teleported into a secret tunnel.
Don't dawdle. The game gives you a timer once you're inside that tunnel. If you mess up the next part, you get booted out and have to wait for the next round to try again.
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Solving the Symbol Puzzle
Inside the tunnel, you'll see a pedestal. Place your sword on it.
Suddenly, symbols will start floating in the air like some kind of magical strobe light. This is the make-or-break moment for the lion bastard sword upgrade. Look at the side of the pedestal itself. It will show you a specific symbol.
You have to shoot the floating symbol that matches the one on the pedestal.
There are four symbols in total. The order usually goes from the top of the pedestal down to the bottom. Shoot one, the pedestal updates to the next one, you find that one in the air, and shoot it too. Do this four times without missing or hitting the wrong one, and the pedestal will flare up.
Grab the sword. You now have the Solais.
Is the Solais Actually Worth It?
The upgraded Solais isn't just a sword anymore. It’s a defensive powerhouse. When you use its ultimate charge, it creates a literal invincibility barrier around you.
Zombies hit the barrier, they die. You stay safe.
The duration of this shield is actually tied to how many hits it takes. If no one touches you, it stays up for a good while. If you're being swarmed by fifty zombies at once, it’ll drain faster, but it gives you that crucial window to reload or get out of a corner. To refill the charge, you just go back to killing zombies with the blade.
It’s way better than the standard Bastard Sword found in games like Elden Ring, where "upgrading" just means dumping Smithing Stones into it at a forge. In BO6, this is a transformation.
Actionable Insights for High Rounds
- Vampiric Augment: If you're running this in later rounds, use the Vampiric Machiatto augment. It turns the sword into a life-leeching machine.
- Don't Shoot the Bugs: I cannot stress this enough. If your teammates are shooting the yellow parasites with their Wonder Weapons, you won't get your sword charge. Tell them to back off until you finish your four door hits.
- The Order Matters: On the pedestal, the symbols are listed vertically. Start with the top one. If the symbols respawn or reset, you shot the wrong one.
- The Barrier Strategy: Use the Solais barrier specifically when you're reviving a teammate. It’s the safest way to get someone up in the middle of a chaotic round.
Once you’ve grabbed the Solais from the pedestal, you’re basically a walking tank. Just remember to keep an eye on your charge meter; a sword that isn't glowing is just a piece of metal, and at round 40, a piece of metal won't save you from a Super Sprinter.