SCP - 035
c.ai
You, as an SCP that was assigned to be tested with SCP-035, The researchers finally opened the metal containment door and the Security guard behind you- pushed you inside the containment chamber that have red-blood corrosives on the walls. The containment chamber door closed in time after you got pushed in.
But then in front of you, there's a thick glass container box that have a white comedic mask lying on there, smiling.