This is what happens when you break off a valve head in a turbo Outback...
There was no coolant in the cooling system. It either washed the pistons off very well or it is a newish motor. Me and my tech are going with the former since it is a junkyard STI (pretty much same and OBK turbo) motor in it.
And there is the carnage
Yeah.... Dropped the valve head, split the piston, broke the bore wall, filled the engine with so much debris that it transferred sides through the intake to the opposite side, and basically ruined the engine. Lets just say it wasn’t a cheap estimate.