A machine with intelligence greater than the sum of all human intelligence to have ever existed
Experts in the field almost unanimously agreeing in this prospect as not just a dream but an inevitability.
No way to control its development because AI technology is stratified among various international groups and markets
The fact that when a superintelligence is finally born it will be aware of its inherent threat to humanity and try to hide its power
The fact that if it recognizes our existence as a threat to itself it could literally wave it's magic wand and we'd all be dead
I try not to think about it tho!