SCP-939, a Voice Changeling that uses the voice of its victims to draw more prey near in order to devour them.

Presumably these are some of his victims, kept alive indefinitely so he can torture them at his leisure.

And I Must Scream: One room in SCP-106 's Pocket Dimension is filled with what look like coffins, from which muffled sobs and whispers can be heard.

Amplifier Artifact: SCP-914 when set on Fine or Very Fine, though this can backfire depending on the object.

Having read the wiki and knowing what the designations refer to helps immensely in avoiding walking into rooms with murderous occupants.

All There in the Manual: While the game does provide documents explaining the nature of the SCPs you come across, getting those generally requires entering the cells in the first place.

Affably Evil: SCP-049, judging from his quotes.

The game's version of the character became invoked Ascended Fanon when 049's article was rewritten in May 2018, not only making this personality change official but bringing back the same voice actor, TheVolgun, to read his lines.

At the time he was added to the game, his entry on the wiki characterized him as a Silent Antagonist with a sense of Blue-and-Orange Morality despite this, the game made him more of a Cold Ham who is quite chatty while pursuing the player around the facility.

Adaptation Personality Change: An interesting example with SCP-049.

SCP: Containment Breach contains examples of:

Scp containment breach maps