Darius is extremely arrogant and is taking full advantage of his base's position on Nonuel—a secondary source of element zero—to extort from the Alliance. If Commander Shepard is mostly Renegade, Admiral Hackett sends Shepard to negotiate with Darius.
Darius is clearly insulted by Shepard's presence and begins on a hostile note, before making outrageous demands. At any point in the conversation, Shepard can tire of Darius and start shooting. During the negotiations, Shepard only has the opportunity to object to one of Darius' conditions (including asking that the Alliance provide him with equipment to make red sand). If Shepard objects more than once, Darius will declare the negotiations over and order his men to attack.
If Shepard does make an objection, Darius angrily claims that he is, in fact, an ally of the Alliance. After the batarians were driven out of the Skyllian Verge, the Alliance supplied weapons and equipment to him so Darius's syndicate, the most powerful in the area, could take over and stabilise the region. Now the Alliance is reneging on its 'partnership' because of Darius's greed regarding element zero and drug operations.
By the end of the negotiation, Darius has one last condition: he wants Shepard to say "please".
Once the negotiations are complete Shepard can report back to Admiral Hackett. Whether Darius survives or not, Shepard will realise that Hackett expected and even wanted the Commander to kill Darius. Hackett claims Shepard should not be surprised: "or did you think you were the only one who did whatever was necessary to get the job done?"
- Darius possesses higher health than his Retainers and has five bars of shielding. Both of these will regenerate over time and he can use Immunity for further protection. On Insanity, he will also gain Shield Boost.
- Darius is equipped with an assault rifle and a shotgun and will switch between them depending on the range. Using Sabotage against him will simply make him switch from his current weapon. He can also launch Carnage when he is equipped with a shotgun.
- While he's more powerful and durable than his Retainers, they will still deal more damage due to their numbers. As such, it might be a good idea to put Darius in the Stasis field and whittle down retainers with all your weapons and powers before he can rejoin the fight.
- Even better, as soon as the fight begins, you can use Overload to detonate hazardous containers behind him and potentially blast him off his balcony, giving you a humourous chance to take him out of the fight quickly and easily.
- Unused audio files indicate that had Shepard eliminated Darius, various pirate factions would attempt to halt Alliance mining only for the efforts to be vain. If Shepard spared Darius, the price for element zero will have been inflated due to Darius's demands.
- Darius is voiced by Townsend Coleman.