unidentified mass

Scp 4781
Object Class: Euclid
Scp 4781 is to be kept in a 15x14 ft observation area with reinforced mirrors looking in. The floor and walls will also be concrete and coated in lead.

Description:
Scp 4781 appears to be a black corrosive ooze with a tar-like appearance. The exact shape is approximated to be that of unbaked dough, The diameter is estimated at about the size of a round table. The tar on occasion has bubbled at certain temperatures. A grey substance has been seen moving through the specimen in fixed intervals while scientists were doing a closer examination. This grey substance has been tested and has been determined that it has a very similar chemical compound as adrenaline.
The substance was put in a syringe and tested on D-90567, the subject gained an extraordinary amount of energy for 15 seconds and then suffered a heart attack. It has been perceived that this must be the blood of an extraordinarily large unidentified creature when it was in a state of hyperactivity or hypertension. The ooze was found in a runoff of the Dnieper river, at first, it was speculated that it was a variant of the Elephant's Foot, a highly radioactive clump of Corium that was one of the results of the Chernobyl incident, hence the lead-coated walls. Although, further research has concluded that this is no blob of Corium. To the more intelligent SCPs, this substance has some kind of foreboding presence. When scientist Alan(REDACTED) and James(REDACTED) engaged in conversation about the entity in front of SCP-682's cell, 682 got noticeably distressed and appeared to move around in discomfort.

It is widely believed now that this is the blood of a large entity, the exact whereabouts of this entity is still unknown, but further testing is to be put into action to learn the specifics.