Jiang Ran didn't seem particularly surprised by the sudden change in the old man from Room 301. Instead, he responded with playful sarcasm:

"Old man, your back healed up? You should thank me! Must be my cooking was so good it cured your back problems."

The old man from Room 301 stood up with a wrinkly smile that squeezed his entire face. 

"That's right, thanks to you, young man. So to show my gratitude, let me treat you to some steamed buns."

No sooner had he stood up than the old man suddenly attacked. His right fist shot out like lightning. Even disregarding the force behind it, the sheer speed of the punch surpassed what most twenty-somethings could manage. 

But what happened next was even more astonishing. As the fist came at him, Jiang Ran simultaneously rose to his feet and threw a counterpunch with equally fluid, lightning-fast movements.

BAM!

Their fists collided violently. Jiang Ran calmly withdrew his hand afterward, completely unfazed, while the old man's entire arm trembled uncontrollably, his face twitching several times.

"Not bad, kid. I underestimated you. Didn't expect you to be a trained fighter."

"Haha, likewise, old man. Who would've thought not only was your back injury fake, but your martial skills are nothing to scoff at either!"

After three seconds of intense eye contact, the two suddenly launched at each other like mortal enemies.

Like some other apartments, Room 301 had soundproofing. So despite their life-and-death struggle creating massive commotion, none of the other residents noticed.

But the live stream audience saw everything. Though it was already 3 AM, many viewers remained awake due to the earlier manhunt events and now witnessed this brutal fight unfolding live.

The chat exploded with comments:

[Damn! Jiang Ran's current personality is ridiculously strong! He's actually trading blows with that old man!]

[No kidding! That old man fights like a demon - definitely professionally trained. I run a martial arts school, and his techniques are legit!]

[This is insane! More exciting than any martial arts movie! So damn satisfying!]

[Right? Remember how this old bastard slaughtered those five victims like chickens? Always playing weak. Serves him right to finally meet his match!]

The battle raged for a full hour, leaving the living room in shambles. In the end, Jiang Ran remained standing - though covered in wounds, his face swollen. Spitting out blood, he looked down at the far more battered old man gasping on the floor.

"Old man, if you were decades younger at my age, I'd have lost for sure. Pity age caught up with you." 

Before leaving, Jiang Ran considerately called an ambulance for the old man. Originally planning to go out, he instead returned home, physically exhausted from the fight.

But shortly after resting, a cold mechanical voice echoed in his mind:

[Ding! Host no longer in danger. Alternate personality receding. Primary personality resuming control!]

Jiang Ran's eyes turned bloodshot as he cursed: "Dammit! I don't want to go back!"

...

Next morning.

Dawn.

Jiang Ran woke from nightmares to discover his entire body covered in painful injuries. 

"Strange... where did all these wounds come from? And wasn't I trapped in my bedroom by that chainsaw man last night? Was it all a dream?"

Inspecting his bedroom revealed complete disarray. The living room was worse - especially the security door which now looked thoroughly wrecked. Clearly, it hadn't been a dream.

But if not, what happened afterward? And how did he get these injuries?

As he pondered, familiar voices sounded in the hallway. Apartment manager Xiao Zhang entered with a team of workers in uniforms carrying tools and materials.

"Ah, Mr. Jiang Ran! Our deepest apologies for last night's incident and the damages to your home. Rest assured the apartment management will cover all repair costs. We'll have everything fixed up now."

The workers immediately got to work. Scratching his head, Jiang Ran asked Xiao Zhang what exactly had happened last night.

The manager briefly explained: two foreign criminals had targeted Xiao Nuo's classmate, but police intervened and resolved the situation.

Some details still didn't add up for Jiang Ran, but he decided not to dwell on it - at least he was alive. As for his injuries...

Noticing the wounds, Xiao Zhang quickly added: "Mr. Jiang Ran, these must be from last night too. Please get checked at the hospital - we'll cover all medical expenses."

Jiang Ran had planned hospital treatment anyway, so free healthcare was welcome.

The following days passed smoothly. The repair team efficiently restored Jiang Ran's apartment, and all structural damages from that night's manhunt throughout the building were fixed. Hospital checks confirmed only superficial wounds - nothing serious.

More importantly, all this occurred within the last three days of the 25th round's seven-day period. Meaning Jiang Ran had survived the 25th round as a lab rat.

The live stream audience wasn't particularly surprised - that fight had been too intense. Even if it wasn't Jiang Ran's primary personality but an alternate that did the fighting, it proved how incredibly hard he was to kill.

Live stream chat:

Middle-aged Uncle: [Well, the 25th round's over. Now we wait for the 26th. Wonder how many days this time.]

Domineering Female CEO: [There were five days between Rounds 24 and 25 - average pacing for this show! The 26th round can wait!]

Little Dragon Girl: [Stream closes in ten minutes. While Jiang Ran survived Round 25, it'd be a shame if he died in the apartment before Round 26 starts.] 

Many previous lab rats had survived one round only to perish before the next began. After all, when the "Neighbors Over Distant Relatives" live stream ended, the apartment's psychopathic killers didn't take vacations.