Now then, I have this idea for a humanoid SCP that, like a few others of the SCP-humans would be indistinguishable from a normal human, with no way apart from an MRI scan or an X-ray scan to show that he's different.
The scans, however, would show a significant difference in the SCP's brain and normal human brains, although he would claim that he thinks like every other person and exhibits an average IQ.
His anomalous properties would be that after an undetermined amount of time after the last time it's activated, he would be obsessed with the acquisition of a canvas of the right size, a number of paintbrushes (specific number and types each time) as well as an absolutely specific amount of paint in various colours.
Once he'd been given or obtained the aforementioned supplies, he would isolate himself and obsessively start painting on the canvas, only ever stopping to eat and not showing any signs of exhaustion or being tired until after the incident would be over.
Each and every painting he paints in this way would show some event that would occur in the next 3-6 months, as if it was a still-frame showing every exact detail of that moment of whatever event it would be.
Foundation testing would show them that the paintings are predictions, not actually manipulating with the course of future events, and if reacted to quickly enough and precisely, they would be capable of preventing the event shown on the painting.
I also have the idea of having an O5-classified section of the SCP that would be a short briefing of the newest painting and how it depicts an XK-class end-of-the-world scenario and how preparations were already under way to hopefully prevent it from happening.