Kael was halfway back to the Hollow when he heard the sound.
A thud. Not large. But wrong.
He paused.
Turned off the path.
And found Riven.
The boy lay slumped against the roots of a gnarled tree, one hand clutching his chest, the other digging weakly into the earth.
His skin was pale.
Too pale.
Veins like ink spilled across his neck.
His breath came in sharp gasps—then stopped.
Then started again.
Kael didn't call for help.
Didn't hesitate.
He knelt beside him and pressed two fingers to Riven's wrist.
Pulse—jagged.
Spiking.
Like something inside was tearing him apart from the center.
He unfastened Riven's outer robe.
Saw the swelling near the heart.
The faint purple lines.
Then the mark.
Small. Circular. Burned near the collarbone.
A sigil.
Faintly glowing green.
Kael's expression didn't change.
But inside, a memory surfaced.
Books.
Warnings.
Old herbal records buried under Elric's stricter teachings.
Lifesurge.
A forbidden blend of body amplifiers and spirit toxins.
Burns years of life in exchange for raw power.
Temporary.
Violent.
And irreversible if overused.
He stared at that faintly glowing sigil, brows tightening.
One passage floated into focus:
"脉毒之药,焚血激骨.服者三日内经络震颤,肌肤泛紫,心律暴走.若见灵印烙骨者,必为'Lifesurge'."
Kael's eyes sharpened. He confirmed it.
Kael moved fast.
Ground frostleaf. Crushed sourvine. A touch of blood from his own thumb.
Mixed, pressed, forced under Riven's tongue.
Held his jaw shut.
Waited.
The boy convulsed.
Then breathed.
Kael leaned back.
But didn't leave.
He waited until Riven's eyes opened.
Dazed.
Groggy.
Then sharp.
He blinked twice, confusion giving way to instinct. His hand shifted subtly toward the saber at his back.
Kael raised his hand calmly. "Don't."
Riven paused.
"I wasn't going to—"
"You were," Kael said. "But you won't."
Riven's eyes narrowed. He glanced down—saw the smudge of dried paste at the edge of his mouth.
Then up again.
"You… did something."
Kael nodded. "I saved your life."
Riven's hand curled tighter, but didn't move.
Kael continued, voice even. "I've read about that mark. It's drawn in the same pattern as the forbidden amplifiers from the border archives. Lifesurge."
Riven stiffened. Didn't confirm. Didn't deny.
Kael's tone didn't change.
"I know what it costs. What it does. And how to slow the damage."
A pause.
Then:
"You want something."
Kael didn't smile.
But something cold flickered behind his eyes.
"I want to not be the one lying here next time."
Riven's brow furrowed.
Kael continued, voice calm.
"I'll make you a stabilizer. Every month. Enough to keep you from dying. Or going mad."
"Where do I get it?" Riven asked.
"I'll leave the first dose near the dried well behind the eastern cliff path," Kael said. "Third day of each month. Take it or don't. I won't wait."
Kael met his eyes for a beat, then added, "And I won't hand it to you in person."
Riven raised a brow.
Kael's tone was even. "You don't want to be seen coming to me. And I don't want others asking why I'd care."
He didn't elaborate. But both of them understood.
This wasn't friendship.
It was a transaction.
One best kept hidden.
Riven hesitated. Then asked, more quietly, "How do you know how to do this?"
Kael looked down at the sigil again. "Because I studied what no one else would. And I remember every cure I was told not to touch."
"You think I trust you just because you saved me?"
Kael's voice didn't waver. "No. But I trust you want to keep living. And right now, I'm your only way to do that."
A pause.
Then, slowly, Riven gave a single nod.
No handshake.
No words.
Just agreement.
Kael stood.
But before turning, he added, "I don't care what you're trying to prove. But if you keep using that poison like a shortcut, you'll never make it to whatever you're chasing."
Riven looked away.
Kael turned to go, but Riven called after him.
"I tried everything else. The normal ways... they weren't enough. No one saw me. Not until I started winning."
Kael didn't look back. "Then you should understand why I made you that deal."
And for the first time since entering the Hollow, he didn't feel small.
Not entirely.
Far beneath his robe, the bottle pulsed once.
Not in approval.
Not in protest.
Just acknowledgment.