"And when he escapes?"

"If," Eris corrected.

"When he escapes," Sloane continued, "he'll have torn a hole straight through your throne world and into the Dreadnaught. This entire place will be compromised, and the City with it. You're fine with that risk?"

"There is always risk," Eris said. "You must assume risk inherent with trust, and focus."

The words were pointed.

"That's not how trust works," Sloane said, unclenching her jaw with some effort.

"No?" Eris's sidelong glance was too green. It made something itch in Sloane that she didn't like. "Tell me of trust, Deputy Commander Sloane."

"It's earned." Sloane uncrossed her arms. Crossed them again, the other way this time. "Someone does the work, again and again. Proves they have the skills and the follow-through to get a job done. It adds up, over time. Long enough, and you know someone can and will do what they say they will. Then you don't have to question when they promise you the impossible, because you know they've got a way. That's certainty. That's trust."

"I see." Eris sounded like she was trying too hard to be neutral. She laid solid, unwavering lines into the floor of her throne-library, one after another. Unhesitating.

Sloane's arm burned. She ignored it.

"Trust," Eris said at length, "is always, still, a risk. It is whispering a secret to another and hoping they will not tell it. They do not—you are caught before you fall. This time. And ever after, you must ask yourself: Is this the step too far? Is this secret the one that turns them back? But you will never know, not completely, that they will not. To entirely understand someone is impossible. You can only guess, and hope, and trust."

"You sound like Savathûn," Sloane told her, and regretted it immediately. It wasn't true—she just hated the twistiness of Eris's mind, the way it spiraled around a question that should be so easy to answer.

Eris's chitin-plated shoulders hitched, but her back was to Sloane, and it was hard to tell if she felt anything serious about the accusation. "We must do something, Deputy Commander. I trust," she stressed the word lightly, "that you will be there to chide me if I fail."

Sloane's lip curled. "I'll be there," she said. "But to grind the Echo into dust. That's more important than anything else—making sure it's taken care of."

"There you have it." Eris turned, then, a lightness on her face that Sloane had rarely seen before. "You are a certainty. Above the risk, I know this: you will not allow this to go unfinished."

That was not quite the lesson Sloane had hoped Eris would take away from this conversation. "I'm only one Titan," Sloane said seriously. "If and when he escapes you, we're going to need more firepower than that."

Eris hesitated. Only briefly, but it was the closest to a win Sloane was going to get. "Then make what preparations you must," she said. "Warn whom you feel prudent. I will do this—I must do this. I am aware of the risk; I would not proceed if it was not well-founded."

The reward for a job well done was always more work, wasn't it? "Fine," Sloane said through gritted teeth.

At least Eris trusted her, by one definition or another. It wasn't nothing.