Lord of Mordor
"Your forces await your command. The time has come to launch your assault againts The Black Hand."
Once all five Warchiefs are yours and you’re ready to get your revenge against the remaining Black Captains, head to the the mission start, which is on the southern end of the western-most docks in Watcher’s Landing. A smuggler is meeting with Marwen and Lithariel, who apparently conscripted some smugglers, who are willing to carry you and your Uruk army to your destination. Marwen and Lithariel exchange concerns and farwells with Talion before he sets sail.
When you land you’ll be confronted by an Uruk named Bagabug the Sneak, who gives a rousing speech to his troops. Talion responds in kind, and battle is joined. Bagabug is invulnerable to stealth and ranged attacks, and has the "No Chance" and "Deadly" Strengths, making him somewhat of a threat if you’re not careful. Don’t give him the opportunity to stand back and pelt you with javelins. When he’s dead his Uruks will disperse. Grab his Rune and head south-east with your surviving Uruks to continue the fight.
Continue into a fort and climb your way through the courtyard and into the keep. A disembodied voice will speak to Talion, and Celebrimbor will identify the voice as The Tower. The Tower plays some hide-and-seek mind games with Talion before appearing, then makes offers to both Talion and Celembrimbor before revealing that Celebrimbor apparently chose you as a host, and can end the possession at any time. Seeing that a fight is inevitable, The Tower vanishes. No time to fight with the Wraith right now-first we’ll deal the The Tower, then the Black Hand, then we can worry about Celembrimbor.
You’ll have eight minutes to hunt down the Tower, who has many simulacrums wandering around in the courtyard. Your goal is to Stealth Drain him, which will suck out somewhat more than a quarter of his health each time. By now, this should be child’s play, considering how often we’ve used Stealth in more challenging situations in the past. He looks around fairly often, and will wander around idlely, but otherwise, he shouldn’t be hard to Drain. Do this three times and you’ll be called back to the keep by the disembodied voice of your dead wife… which of course, is The Tower using another illusion. When you approach the Tower reveals himself, and you’ll have to succeed at the easiest QTE in the game-just hold down the (Circle) button to counter The Tower’s brand. When successful, Talion will brutralize The Tower and dispatch him.
After the fight, Talion breaks the order of operations by arguing with Celebrimbor. The Wraith points out that gaining revenge is better than simply dying with his family, and to that Talion agrees. The Black Hand is the next target.