Worf

But first, I'll have to teach you something the Changelings wanted.

Starfleet is a family. We Klingons honor family and they are my friends, part of my House.

Into this new golem will go a bit of Lal, B-4... of Lore. And, of course, a great deal of Data..
This time with the wisdom and true human aesthetic of age.
With the hope that in totality, something... someone... Will rise to be the best of us.
It appears Altan Soong died before he was able to complete the project.
The integration effort failed. All the personalities remain at odds inside this vessel.
[... Jean Luc Picard]

What, exactly, are they storing here?
Many of Section 31's most nefarious table scraps, it would seem. Section 31?
Critical division of Starfleet Intelligence.

Welcome, Daystrom visitors. Please identify.
Worf, the key.
Welcome, Daystrom visitors.
We've got about seconds before that thing stops asking nicely. Please identify.
Welcome, Daystrom visitors. Please identify.
Daystrom visitors, please identify yourselves immediately or lethal security protocols will engage.
Thank you. Thank you. Have a wonderful day. And please, no food or beverags in the research area.
Alarm sounding...
They found us.
How?

I hope this key works. Otherwise, we're going to have to resort to some old-fashioned Klingon offence.
Captain Riker...
Worf, call me Will. Come on.
You should know that I now prefer pacifism to actual combat. Energize.
We're all gonna die.

Since the break-in, the station has been mostly unoccupied. It is patrolled by Starfleet security every hour, but the vault itself is protected by an astonishingly lethal AI system. One that thinks, that adapts.
Fortunately, we have acquired a key that should temporarily disable the system. Unfortunately, if this key fails...
Well, instead of finding one weapon, we'll be on the wrong end of many.

It appears our old enemy, the Changelings, have re-emerged from the wake of the Dominion War. During the war, they attacked the Federation with deception and might, and we retaliated with a Starfleet-made virus. There are scars and shame on both sides. Starfleet did, however, deliver the cure to the Changeling home world, to the Great Link. Not without weaponizing a few zealots in the process.